preserve tool definition and call JSON ordering (#13525)

* preserve tool definition and call JSON ordering

This is another iteration of
<https://github.com/ollama/ollama/pull/12518>, but this time we've
simplified things by relaxing the competing requirements of being
compatible AND order-preserving with templates (vs. renderers). We
maintain backwards compatibility at the cost of not guaranteeing order
for templates. We plan on moving more and more models to renderers,
which have been updated to use these new data types, and additionally
we could add an opt-in way of templates getting an order-preserved list
(e.g., via sibling template vars)

* orderedmap_test: remove testify

api/types.go

@@ -3,6 +3,7 @@ package api
 import (
 	"encoding/json"
 	"fmt"
+	"iter"
 	"log/slog"
 	"math"
 	"os"
@@ -14,6 +15,7 @@ import (
 	"github.com/google/uuid"
 
 	"github.com/ollama/ollama/envconfig"
+	"github.com/ollama/ollama/internal/orderedmap"
 	"github.com/ollama/ollama/types/model"
 )
 
@@ -227,13 +229,79 @@ type ToolCallFunction struct {
 	Arguments ToolCallFunctionArguments `json:"arguments"`
 }
 
-type ToolCallFunctionArguments map[string]any
+// ToolCallFunctionArguments holds tool call arguments in insertion order.
+type ToolCallFunctionArguments struct {
+	om *orderedmap.Map[string, any]
+}
+
+// NewToolCallFunctionArguments creates a new empty ToolCallFunctionArguments.
+func NewToolCallFunctionArguments() ToolCallFunctionArguments {
+	return ToolCallFunctionArguments{om: orderedmap.New[string, any]()}
+}
+
+// Get retrieves a value by key.
+func (t *ToolCallFunctionArguments) Get(key string) (any, bool) {
+	if t == nil || t.om == nil {
+		return nil, false
+	}
+	return t.om.Get(key)
+}
+
+// Set sets a key-value pair, preserving insertion order.
+func (t *ToolCallFunctionArguments) Set(key string, value any) {
+	if t == nil {
+		return
+	}
+	if t.om == nil {
+		t.om = orderedmap.New[string, any]()
+	}
+	t.om.Set(key, value)
+}
+
+// Len returns the number of arguments.
+func (t *ToolCallFunctionArguments) Len() int {
+	if t == nil || t.om == nil {
+		return 0
+	}
+	return t.om.Len()
+}
+
+// All returns an iterator over all key-value pairs in insertion order.
+func (t *ToolCallFunctionArguments) All() iter.Seq2[string, any] {
+	if t == nil || t.om == nil {
+		return func(yield func(string, any) bool) {}
+	}
+	return t.om.All()
+}
+
+// ToMap returns a regular map (order not preserved).
+func (t *ToolCallFunctionArguments) ToMap() map[string]any {
+	if t == nil || t.om == nil {
+		return nil
+	}
+	return t.om.ToMap()
+}
 
 func (t *ToolCallFunctionArguments) String() string {
-	bts, _ := json.Marshal(t)
+	if t == nil || t.om == nil {
+		return "{}"
+	}
+	bts, _ := json.Marshal(t.om)
 	return string(bts)
 }
 
+func (t *ToolCallFunctionArguments) UnmarshalJSON(data []byte) error {
+	t.om = orderedmap.New[string, any]()
+	return json.Unmarshal(data, t.om)
+}
+
+func (t ToolCallFunctionArguments) MarshalJSON() ([]byte, error) {
+	if t.om == nil {
+		return []byte("{}"), nil
+	}
+	return json.Marshal(t.om)
+}
+
 type Tool struct {
 	Type     string       `json:"type"`
 	Items    any          `json:"items,omitempty"`
@@ -282,13 +350,78 @@ func (pt PropertyType) String() string {
 	return fmt.Sprintf("%v", []string(pt))
 }
 
+// ToolPropertiesMap holds tool properties in insertion order.
+type ToolPropertiesMap struct {
+	om *orderedmap.Map[string, ToolProperty]
+}
+
+// NewToolPropertiesMap creates a new empty ToolPropertiesMap.
+func NewToolPropertiesMap() *ToolPropertiesMap {
+	return &ToolPropertiesMap{om: orderedmap.New[string, ToolProperty]()}
+}
+
+// Get retrieves a property by name.
+func (t *ToolPropertiesMap) Get(key string) (ToolProperty, bool) {
+	if t == nil || t.om == nil {
+		return ToolProperty{}, false
+	}
+	return t.om.Get(key)
+}
+
+// Set sets a property, preserving insertion order.
+func (t *ToolPropertiesMap) Set(key string, value ToolProperty) {
+	if t == nil {
+		return
+	}
+	if t.om == nil {
+		t.om = orderedmap.New[string, ToolProperty]()
+	}
+	t.om.Set(key, value)
+}
+
+// Len returns the number of properties.
+func (t *ToolPropertiesMap) Len() int {
+	if t == nil || t.om == nil {
+		return 0
+	}
+	return t.om.Len()
+}
+
+// All returns an iterator over all properties in insertion order.
+func (t *ToolPropertiesMap) All() iter.Seq2[string, ToolProperty] {
+	if t == nil || t.om == nil {
+		return func(yield func(string, ToolProperty) bool) {}
+	}
+	return t.om.All()
+}
+
+// ToMap returns a regular map (order not preserved).
+func (t *ToolPropertiesMap) ToMap() map[string]ToolProperty {
+	if t == nil || t.om == nil {
+		return nil
+	}
+	return t.om.ToMap()
+}
+
+func (t ToolPropertiesMap) MarshalJSON() ([]byte, error) {
+	if t.om == nil {
+		return []byte("null"), nil
+	}
+	return json.Marshal(t.om)
+}
+
+func (t *ToolPropertiesMap) UnmarshalJSON(data []byte) error {
+	t.om = orderedmap.New[string, ToolProperty]()
+	return json.Unmarshal(data, t.om)
+}
+
 type ToolProperty struct {
-	AnyOf       []ToolProperty          `json:"anyOf,omitempty"`
+	AnyOf       []ToolProperty     `json:"anyOf,omitempty"`
-	Type        PropertyType            `json:"type,omitempty"`
+	Type        PropertyType       `json:"type,omitempty"`
-	Items       any                     `json:"items,omitempty"`
+	Items       any                `json:"items,omitempty"`
-	Description string                  `json:"description,omitempty"`
+	Description string             `json:"description,omitempty"`
-	Enum        []any                   `json:"enum,omitempty"`
+	Enum        []any              `json:"enum,omitempty"`
-	Properties  map[string]ToolProperty `json:"properties,omitempty"`
+	Properties  *ToolPropertiesMap `json:"properties,omitempty"`
 }
 
 // ToTypeScriptType converts a ToolProperty to a TypeScript type string
@@ -337,11 +470,11 @@ func mapToTypeScriptType(jsonType string) string {
 }
 
 type ToolFunctionParameters struct {
-	Type       string                  `json:"type"`
+	Type       string             `json:"type"`
-	Defs       any                     `json:"$defs,omitempty"`
+	Defs       any                `json:"$defs,omitempty"`
-	Items      any                     `json:"items,omitempty"`
+	Items      any                `json:"items,omitempty"`
-	Required   []string                `json:"required,omitempty"`
+	Required   []string           `json:"required,omitempty"`
-	Properties map[string]ToolProperty `json:"properties"`
+	Properties *ToolPropertiesMap `json:"properties"`
 }
 
 func (t *ToolFunctionParameters) String() string {

api/types_test.go

@@ -11,6 +11,24 @@ import (
 	"github.com/stretchr/testify/require"
 )
 
+// testPropsMap creates a ToolPropertiesMap from a map (convenience function for tests, order not preserved)
+func testPropsMap(m map[string]ToolProperty) *ToolPropertiesMap {
+	props := NewToolPropertiesMap()
+	for k, v := range m {
+		props.Set(k, v)
+	}
+	return props
+}
+
+// testArgs creates ToolCallFunctionArguments from a map (convenience function for tests, order not preserved)
+func testArgs(m map[string]any) ToolCallFunctionArguments {
+	args := NewToolCallFunctionArguments()
+	for k, v := range m {
+		args.Set(k, v)
+	}
+	return args
+}
+
 func TestKeepAliveParsingFromJSON(t *testing.T) {
 	tests := []struct {
 		name string
@@ -309,9 +327,9 @@ func TestToolFunctionParameters_MarshalJSON(t *testing.T) {
 			input: ToolFunctionParameters{
 				Type:     "object",
 				Required: []string{"name"},
-				Properties: map[string]ToolProperty{
+				Properties: testPropsMap(map[string]ToolProperty{
 					"name": {Type: PropertyType{"string"}},
-				},
+				}),
 			},
 			expected: `{"type":"object","required":["name"],"properties":{"name":{"type":"string"}}}`,
 		},
@@ -319,9 +337,9 @@ func TestToolFunctionParameters_MarshalJSON(t *testing.T) {
 			name: "no required",
 			input: ToolFunctionParameters{
 				Type: "object",
-				Properties: map[string]ToolProperty{
+				Properties: testPropsMap(map[string]ToolProperty{
 					"name": {Type: PropertyType{"string"}},
-				},
+				}),
 			},
 			expected: `{"type":"object","properties":{"name":{"type":"string"}}}`,
 		},
@@ -339,7 +357,7 @@ func TestToolFunctionParameters_MarshalJSON(t *testing.T) {
 func TestToolCallFunction_IndexAlwaysMarshals(t *testing.T) {
 	fn := ToolCallFunction{
 		Name:      "echo",
-		Arguments: ToolCallFunctionArguments{"message": "hi"},
+		Arguments: testArgs(map[string]any{"message": "hi"}),
 	}
 
 	data, err := json.Marshal(fn)
@@ -529,7 +547,7 @@ func TestToolPropertyNestedProperties(t *testing.T) {
 			expected: ToolProperty{
 				Type:        PropertyType{"object"},
 				Description: "Location details",
-				Properties: map[string]ToolProperty{
+				Properties: testPropsMap(map[string]ToolProperty{
 					"address": {
 						Type:        PropertyType{"string"},
 						Description: "Street address",
@@ -538,7 +556,7 @@ func TestToolPropertyNestedProperties(t *testing.T) {
 						Type:        PropertyType{"string"},
 						Description: "City name",
 					},
-				},
+				}),
 			},
 		},
 		{
@@ -566,22 +584,22 @@ func TestToolPropertyNestedProperties(t *testing.T) {
 			expected: ToolProperty{
 				Type:        PropertyType{"object"},
 				Description: "Event",
-				Properties: map[string]ToolProperty{
+				Properties: testPropsMap(map[string]ToolProperty{
 					"location": {
 						Type:        PropertyType{"object"},
 						Description: "Location",
-						Properties: map[string]ToolProperty{
+						Properties: testPropsMap(map[string]ToolProperty{
 							"coordinates": {
 								Type:        PropertyType{"object"},
 								Description: "GPS coordinates",
-								Properties: map[string]ToolProperty{
+								Properties: testPropsMap(map[string]ToolProperty{
 									"lat": {Type: PropertyType{"number"}, Description: "Latitude"},
 									"lng": {Type: PropertyType{"number"}, Description: "Longitude"},
-								},
+								}),
 							},
-						},
+						}),
 					},
-				},
+				}),
 			},
 		},
 	}
@@ -591,7 +609,13 @@ func TestToolPropertyNestedProperties(t *testing.T) {
 			var prop ToolProperty
 			err := json.Unmarshal([]byte(tt.input), &prop)
 			require.NoError(t, err)
-			assert.Equal(t, tt.expected, prop)
+
+			// Compare JSON representations since pointer comparison doesn't work
+			expectedJSON, err := json.Marshal(tt.expected)
+			require.NoError(t, err)
+			actualJSON, err := json.Marshal(prop)
+			require.NoError(t, err)
+			assert.JSONEq(t, string(expectedJSON), string(actualJSON))
 
 			// Round-trip test: marshal and unmarshal again
 			data, err := json.Marshal(prop)
@@ -600,7 +624,10 @@ func TestToolPropertyNestedProperties(t *testing.T) {
 			var prop2 ToolProperty
 			err = json.Unmarshal(data, &prop2)
 			require.NoError(t, err)
-			assert.Equal(t, tt.expected, prop2)
+
+			prop2JSON, err := json.Marshal(prop2)
+			require.NoError(t, err)
+			assert.JSONEq(t, string(expectedJSON), string(prop2JSON))
 		})
 	}
 }
@@ -616,12 +643,12 @@ func TestToolFunctionParameters_String(t *testing.T) {
 			params: ToolFunctionParameters{
 				Type:     "object",
 				Required: []string{"name"},
-				Properties: map[string]ToolProperty{
+				Properties: testPropsMap(map[string]ToolProperty{
 					"name": {
 						Type:        PropertyType{"string"},
 						Description: "The name of the person",
 					},
-				},
+				}),
 			},
 			expected: `{"type":"object","required":["name"],"properties":{"name":{"type":"string","description":"The name of the person"}}}`,
 		},
@@ -638,7 +665,7 @@ func TestToolFunctionParameters_String(t *testing.T) {
 					s.Self = s
 					return s
 				}(),
-				Properties: map[string]ToolProperty{},
+				Properties: testPropsMap(map[string]ToolProperty{}),
 			},
 			expected: "",
 		},
@@ -651,3 +678,235 @@ func TestToolFunctionParameters_String(t *testing.T) {
 		})
 	}
 }
+
+func TestToolCallFunctionArguments_OrderPreservation(t *testing.T) {
+	t.Run("marshal preserves insertion order", func(t *testing.T) {
+		args := NewToolCallFunctionArguments()
+		args.Set("zebra", "z")
+		args.Set("apple", "a")
+		args.Set("mango", "m")
+
+		data, err := json.Marshal(args)
+		require.NoError(t, err)
+
+		// Should preserve insertion order, not alphabetical
+		assert.Equal(t, `{"zebra":"z","apple":"a","mango":"m"}`, string(data))
+	})
+
+	t.Run("unmarshal preserves JSON order", func(t *testing.T) {
+		jsonData := `{"zebra":"z","apple":"a","mango":"m"}`
+
+		var args ToolCallFunctionArguments
+		err := json.Unmarshal([]byte(jsonData), &args)
+		require.NoError(t, err)
+
+		// Verify iteration order matches JSON order
+		var keys []string
+		for k := range args.All() {
+			keys = append(keys, k)
+		}
+		assert.Equal(t, []string{"zebra", "apple", "mango"}, keys)
+	})
+
+	t.Run("round trip preserves order", func(t *testing.T) {
+		original := `{"z":1,"a":2,"m":3,"b":4}`
+
+		var args ToolCallFunctionArguments
+		err := json.Unmarshal([]byte(original), &args)
+		require.NoError(t, err)
+
+		data, err := json.Marshal(args)
+		require.NoError(t, err)
+
+		assert.Equal(t, original, string(data))
+	})
+
+	t.Run("String method returns ordered JSON", func(t *testing.T) {
+		args := NewToolCallFunctionArguments()
+		args.Set("c", 3)
+		args.Set("a", 1)
+		args.Set("b", 2)
+
+		assert.Equal(t, `{"c":3,"a":1,"b":2}`, args.String())
+	})
+
+	t.Run("Get retrieves correct values", func(t *testing.T) {
+		args := NewToolCallFunctionArguments()
+		args.Set("key1", "value1")
+		args.Set("key2", 42)
+
+		v, ok := args.Get("key1")
+		assert.True(t, ok)
+		assert.Equal(t, "value1", v)
+
+		v, ok = args.Get("key2")
+		assert.True(t, ok)
+		assert.Equal(t, 42, v)
+
+		_, ok = args.Get("nonexistent")
+		assert.False(t, ok)
+	})
+
+	t.Run("Len returns correct count", func(t *testing.T) {
+		args := NewToolCallFunctionArguments()
+		assert.Equal(t, 0, args.Len())
+
+		args.Set("a", 1)
+		assert.Equal(t, 1, args.Len())
+
+		args.Set("b", 2)
+		assert.Equal(t, 2, args.Len())
+	})
+
+	t.Run("empty args marshal to empty object", func(t *testing.T) {
+		args := NewToolCallFunctionArguments()
+		data, err := json.Marshal(args)
+		require.NoError(t, err)
+		assert.Equal(t, `{}`, string(data))
+	})
+
+	t.Run("zero value args marshal to empty object", func(t *testing.T) {
+		var args ToolCallFunctionArguments
+		assert.Equal(t, "{}", args.String())
+	})
+}
+
+func TestToolPropertiesMap_OrderPreservation(t *testing.T) {
+	t.Run("marshal preserves insertion order", func(t *testing.T) {
+		props := NewToolPropertiesMap()
+		props.Set("zebra", ToolProperty{Type: PropertyType{"string"}})
+		props.Set("apple", ToolProperty{Type: PropertyType{"number"}})
+		props.Set("mango", ToolProperty{Type: PropertyType{"boolean"}})
+
+		data, err := json.Marshal(props)
+		require.NoError(t, err)
+
+		// Should preserve insertion order, not alphabetical
+		expected := `{"zebra":{"type":"string"},"apple":{"type":"number"},"mango":{"type":"boolean"}}`
+		assert.Equal(t, expected, string(data))
+	})
+
+	t.Run("unmarshal preserves JSON order", func(t *testing.T) {
+		jsonData := `{"zebra":{"type":"string"},"apple":{"type":"number"},"mango":{"type":"boolean"}}`
+
+		var props ToolPropertiesMap
+		err := json.Unmarshal([]byte(jsonData), &props)
+		require.NoError(t, err)
+
+		// Verify iteration order matches JSON order
+		var keys []string
+		for k := range props.All() {
+			keys = append(keys, k)
+		}
+		assert.Equal(t, []string{"zebra", "apple", "mango"}, keys)
+	})
+
+	t.Run("round trip preserves order", func(t *testing.T) {
+		original := `{"z":{"type":"string"},"a":{"type":"number"},"m":{"type":"boolean"}}`
+
+		var props ToolPropertiesMap
+		err := json.Unmarshal([]byte(original), &props)
+		require.NoError(t, err)
+
+		data, err := json.Marshal(props)
+		require.NoError(t, err)
+
+		assert.Equal(t, original, string(data))
+	})
+
+	t.Run("Get retrieves correct values", func(t *testing.T) {
+		props := NewToolPropertiesMap()
+		props.Set("name", ToolProperty{Type: PropertyType{"string"}, Description: "The name"})
+		props.Set("age", ToolProperty{Type: PropertyType{"integer"}, Description: "The age"})
+
+		v, ok := props.Get("name")
+		assert.True(t, ok)
+		assert.Equal(t, "The name", v.Description)
+
+		v, ok = props.Get("age")
+		assert.True(t, ok)
+		assert.Equal(t, "The age", v.Description)
+
+		_, ok = props.Get("nonexistent")
+		assert.False(t, ok)
+	})
+
+	t.Run("Len returns correct count", func(t *testing.T) {
+		props := NewToolPropertiesMap()
+		assert.Equal(t, 0, props.Len())
+
+		props.Set("a", ToolProperty{})
+		assert.Equal(t, 1, props.Len())
+
+		props.Set("b", ToolProperty{})
+		assert.Equal(t, 2, props.Len())
+	})
+
+	t.Run("nil props marshal to null", func(t *testing.T) {
+		var props *ToolPropertiesMap
+		data, err := json.Marshal(props)
+		require.NoError(t, err)
+		assert.Equal(t, `null`, string(data))
+	})
+
+	t.Run("ToMap returns regular map", func(t *testing.T) {
+		props := NewToolPropertiesMap()
+		props.Set("a", ToolProperty{Type: PropertyType{"string"}})
+		props.Set("b", ToolProperty{Type: PropertyType{"number"}})
+
+		m := props.ToMap()
+		assert.Equal(t, 2, len(m))
+		assert.Equal(t, PropertyType{"string"}, m["a"].Type)
+		assert.Equal(t, PropertyType{"number"}, m["b"].Type)
+	})
+}
+
+func TestToolCallFunctionArguments_ComplexValues(t *testing.T) {
+	t.Run("nested objects preserve order", func(t *testing.T) {
+		jsonData := `{"outer":{"z":1,"a":2},"simple":"value"}`
+
+		var args ToolCallFunctionArguments
+		err := json.Unmarshal([]byte(jsonData), &args)
+		require.NoError(t, err)
+
+		// Outer keys should be in order
+		var keys []string
+		for k := range args.All() {
+			keys = append(keys, k)
+		}
+		assert.Equal(t, []string{"outer", "simple"}, keys)
+	})
+
+	t.Run("arrays as values", func(t *testing.T) {
+		args := NewToolCallFunctionArguments()
+		args.Set("items", []string{"a", "b", "c"})
+		args.Set("numbers", []int{1, 2, 3})
+
+		data, err := json.Marshal(args)
+		require.NoError(t, err)
+
+		assert.Equal(t, `{"items":["a","b","c"],"numbers":[1,2,3]}`, string(data))
+	})
+}
+
+func TestToolPropertiesMap_NestedProperties(t *testing.T) {
+	t.Run("nested properties preserve order", func(t *testing.T) {
+		props := NewToolPropertiesMap()
+
+		nestedProps := NewToolPropertiesMap()
+		nestedProps.Set("z_field", ToolProperty{Type: PropertyType{"string"}})
+		nestedProps.Set("a_field", ToolProperty{Type: PropertyType{"number"}})
+
+		props.Set("outer", ToolProperty{
+			Type:       PropertyType{"object"},
+			Properties: nestedProps,
+		})
+
+		data, err := json.Marshal(props)
+		require.NoError(t, err)
+
+		// Both outer and inner should preserve order
+		expected := `{"outer":{"type":"object","properties":{"z_field":{"type":"string"},"a_field":{"type":"number"}}}}`
+		assert.Equal(t, expected, string(data))
+	})
+}

app/ui/ui.go

@@ -997,7 +997,7 @@ func (s *Server) chat(w http.ResponseWriter, r *http.Request) error {
 				for _, toolCall := range res.Message.ToolCalls {
 					// continues loop as tools were executed
 					toolsExecuted = true
-					result, content, err := registry.Execute(ctx, toolCall.Function.Name, toolCall.Function.Arguments)
+					result, content, err := registry.Execute(ctx, toolCall.Function.Name, toolCall.Function.Arguments.ToMap())
 					if err != nil {
 						errContent := fmt.Sprintf("Error: %v", err)
 						toolErrMsg := store.NewMessage("tool", errContent, nil)
@@ -1558,13 +1558,13 @@ func convertToOllamaTool(toolSchema map[string]any) api.Tool {
 
 	tool.Function.Parameters.Type = "object"
 	tool.Function.Parameters.Required = []string{}
-	tool.Function.Parameters.Properties = make(map[string]api.ToolProperty)
+	tool.Function.Parameters.Properties = api.NewToolPropertiesMap()
 
 	if schemaProps, ok := toolSchema["schema"].(map[string]any); ok {
 		tool.Function.Parameters.Type = getStringFromMap(schemaProps, "type", "object")
 
 		if props, ok := schemaProps["properties"].(map[string]any); ok {
-			tool.Function.Parameters.Properties = make(map[string]api.ToolProperty)
+			tool.Function.Parameters.Properties = api.NewToolPropertiesMap()
 
 			for propName, propDef := range props {
 				if propMap, ok := propDef.(map[string]any); ok {
@@ -1572,7 +1572,7 @@ func convertToOllamaTool(toolSchema map[string]any) api.Tool {
 						Type:        api.PropertyType{getStringFromMap(propMap, "type", "string")},
 						Description: getStringFromMap(propMap, "description", ""),
 					}
-					tool.Function.Parameters.Properties[propName] = prop
+					tool.Function.Parameters.Properties.Set(propName, prop)
 				}
 			}
 		}

go.mod

@@ -28,6 +28,7 @@ require (
 	github.com/nlpodyssey/gopickle v0.3.0
 	github.com/pdevine/tensor v0.0.0-20240510204454-f88f4562727c
 	github.com/tkrajina/typescriptify-golang-structs v0.2.0
+	github.com/wk8/go-ordered-map/v2 v2.1.8
 	golang.org/x/image v0.22.0
 	golang.org/x/mod v0.30.0
 	golang.org/x/tools v0.38.0
@@ -36,6 +37,8 @@ require (
 
 require (
 	github.com/apache/arrow/go/arrow v0.0.0-20211112161151-bc219186db40 // indirect
+	github.com/bahlo/generic-list-go v0.2.0 // indirect
+	github.com/buger/jsonparser v1.1.1 // indirect
 	github.com/bytedance/sonic/loader v0.1.1 // indirect
 	github.com/chewxy/hm v1.0.0 // indirect
 	github.com/chewxy/math32 v1.11.0 // indirect
@@ -45,6 +48,7 @@ require (
 	github.com/gogo/protobuf v1.3.2 // indirect
 	github.com/google/flatbuffers v24.3.25+incompatible // indirect
 	github.com/kr/text v0.2.0 // indirect
+	github.com/mailru/easyjson v0.7.7 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/rivo/uniseg v0.2.0 // indirect

go.sum

@@ -14,7 +14,11 @@ github.com/apache/arrow/go/arrow v0.0.0-20211112161151-bc219186db40 h1:q4dksr6IC
 github.com/apache/arrow/go/arrow v0.0.0-20211112161151-bc219186db40/go.mod h1:Q7yQnSMnLvcXlZ8RV+jwz/6y1rQTqbX6C82SndT52Zs=
 github.com/arbovm/levenshtein v0.0.0-20160628152529-48b4e1c0c4d0 h1:jfIu9sQUG6Ig+0+Ap1h4unLjW6YQJpKZVmUzxsD4E/Q=
 github.com/arbovm/levenshtein v0.0.0-20160628152529-48b4e1c0c4d0/go.mod h1:t2tdKJDJF9BV14lnkjHmOQgcvEKgtqs5a1N3LNdJhGE=
+github.com/bahlo/generic-list-go v0.2.0 h1:5sz/EEAK+ls5wF+NeqDpk5+iNdMDXrh3z3nPnH1Wvgk=
+github.com/bahlo/generic-list-go v0.2.0/go.mod h1:2KvAjgMlE5NNynlg/5iLrrCCZ2+5xWbdbCW3pNTGyYg=
 github.com/boombuler/barcode v1.0.0/go.mod h1:paBWMcWSl3LHKBqUq+rly7CNSldXjb2rDl3JlRe0mD8=
+github.com/buger/jsonparser v1.1.1 h1:2PnMjfWD7wBILjqQbt530v576A/cAbQvEW9gGIpYMUs=
+github.com/buger/jsonparser v1.1.1/go.mod h1:6RYKKt7H4d4+iWqouImQ9R2FZql3VbhNgx27UK13J/0=
 github.com/bytedance/sonic v1.11.6 h1:oUp34TzMlL+OY1OUWxHqsdkgC/Zfc85zGqw9siXjrc0=
 github.com/bytedance/sonic v1.11.6/go.mod h1:LysEHSvpvDySVdC2f87zGWf6CIKJcAvqab1ZaiQtds4=
 github.com/bytedance/sonic/loader v0.1.1 h1:c+e5Pt1k/cy5wMveRDyk2X4B9hF4g7an8N3zCYjJFNM=
@@ -123,6 +127,7 @@ github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+
 github.com/grpc-ecosystem/grpc-gateway v1.16.0/go.mod h1:BDjrQk3hbvj6Nolgz8mAMFbcEtjT1g+wF4CSlocrBnw=
 github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
 github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
+github.com/josharian/intern v1.0.0/go.mod h1:5DoeVV0s6jJacbCEi61lwdGj/aVlrQvzHFFd8Hwg//Y=
 github.com/json-iterator/go v1.1.12 h1:PV8peI4a0ysnczrg+LtxykD8LfKY9ML6u2jnxaEnrnM=
 github.com/json-iterator/go v1.1.12/go.mod h1:e30LSqwooZae/UwlEbR2852Gd8hjQvJoHmT4TnhNGBo=
 github.com/jung-kurt/gofpdf v1.0.0/go.mod h1:7Id9E/uU8ce6rXgefFLlgrJj/GYY22cpxn+r32jIOes=
@@ -143,6 +148,8 @@ github.com/ledongthuc/pdf v0.0.0-20250511090121-5959a4027728 h1:QwWKgMY28TAXaDl+
 github.com/ledongthuc/pdf v0.0.0-20250511090121-5959a4027728/go.mod h1:1fEHWurg7pvf5SG6XNE5Q8UZmOwex51Mkx3SLhrW5B4=
 github.com/leodido/go-urn v1.4.0 h1:WT9HwE9SGECu3lg4d/dIA+jxlljEa1/ffXKmRjqdmIQ=
 github.com/leodido/go-urn v1.4.0/go.mod h1:bvxc+MVxLKB4z00jd1z+Dvzr47oO32F/QSNjSBOlFxI=
+github.com/mailru/easyjson v0.7.7 h1:UGYAvKxe3sBsEDzO8ZeWOSlIQfWFlxbzLZe7hwFURr0=
+github.com/mailru/easyjson v0.7.7/go.mod h1:xzfreul335JAWq5oZzymOObrkdz5UnU4kGfJJLY9Nlc=
 github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
 github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
 github.com/mattn/go-runewidth v0.0.9/go.mod h1:H031xJmbD/WCDINGzjvQ9THkh0rPKHF+m2gUSrubnMI=
@@ -207,6 +214,8 @@ github.com/twitchyliquid64/golang-asm v0.15.1 h1:SU5vSMR7hnwNxj24w34ZyCi/FmDZTkS
 github.com/twitchyliquid64/golang-asm v0.15.1/go.mod h1:a1lVb/DtPvCB8fslRZhAngC2+aY1QWCk3Cedj/Gdt08=
 github.com/ugorji/go/codec v1.2.12 h1:9LC83zGrHhuUA9l16C9AHXAqEV/2wBQ4nkvumAE65EE=
 github.com/ugorji/go/codec v1.2.12/go.mod h1:UNopzCgEMSXjBc6AOMqYvWC1ktqTAfzJZUZgYf6w6lg=
+github.com/wk8/go-ordered-map/v2 v2.1.8 h1:5h/BUHu93oj4gIdvHHHGsScSTMijfx5PeYkE/fJgbpc=
+github.com/wk8/go-ordered-map/v2 v2.1.8/go.mod h1:5nJHM5DyteebpVlHnWMV0rPz6Zp7+xBAnxjb1X5vnTw=
 github.com/x448/float16 v0.8.4 h1:qLwI1I70+NjRFUR3zs1JPUCgaCXSh3SW62uAKT1mSBM=
 github.com/x448/float16 v0.8.4/go.mod h1:14CWIYCyZA/cWjXOioeEpHeN/83MdbZDRQHoFcYsOfg=
 github.com/xtgo/set v1.0.0 h1:6BCNBRv3ORNDQ7fyoJXRv+tstJz3m1JVFQErfeZz2pY=

integration/tools_test.go

@@ -11,6 +11,15 @@ import (
 	"github.com/ollama/ollama/api"
 )
 
+// testPropsMap creates a ToolPropertiesMap from a map (convenience function for tests)
+func testPropsMap(m map[string]api.ToolProperty) *api.ToolPropertiesMap {
+	props := api.NewToolPropertiesMap()
+	for k, v := range m {
+		props.Set(k, v)
+	}
+	return props
+}
+
 func TestAPIToolCalling(t *testing.T) {
 	initialTimeout := 60 * time.Second
 	streamTimeout := 60 * time.Second
@@ -57,12 +66,12 @@ func TestAPIToolCalling(t *testing.T) {
 						Parameters: api.ToolFunctionParameters{
 							Type:     "object",
 							Required: []string{"location"},
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"location": {
 									Type:        api.PropertyType{"string"},
 									Description: "The city and state, e.g. San Francisco, CA",
 								},
-							},
+							}),
 						},
 					},
 				},

internal/orderedmap/orderedmap.go

@@ -0,0 +1,94 @@
+// Package orderedmap provides a generic ordered map that maintains insertion order.
+// It wraps github.com/wk8/go-ordered-map/v2 to encapsulate the dependency.
+package orderedmap
+
+import (
+	"encoding/json"
+	"iter"
+
+	orderedmap "github.com/wk8/go-ordered-map/v2"
+)
+
+// Map is a generic ordered map that maintains insertion order.
+type Map[K comparable, V any] struct {
+	om *orderedmap.OrderedMap[K, V]
+}
+
+// New creates a new empty ordered map.
+func New[K comparable, V any]() *Map[K, V] {
+	return &Map[K, V]{
+		om: orderedmap.New[K, V](),
+	}
+}
+
+// Get retrieves a value by key.
+func (m *Map[K, V]) Get(key K) (V, bool) {
+	if m == nil || m.om == nil {
+		var zero V
+		return zero, false
+	}
+	return m.om.Get(key)
+}
+
+// Set sets a key-value pair. If the key already exists, its value is updated
+// but its position in the iteration order is preserved. If the key is new,
+// it is appended to the end.
+func (m *Map[K, V]) Set(key K, value V) {
+	if m == nil {
+		return
+	}
+	if m.om == nil {
+		m.om = orderedmap.New[K, V]()
+	}
+	m.om.Set(key, value)
+}
+
+// Len returns the number of entries.
+func (m *Map[K, V]) Len() int {
+	if m == nil || m.om == nil {
+		return 0
+	}
+	return m.om.Len()
+}
+
+// All returns an iterator over all key-value pairs in insertion order.
+func (m *Map[K, V]) All() iter.Seq2[K, V] {
+	return func(yield func(K, V) bool) {
+		if m == nil || m.om == nil {
+			return
+		}
+		for pair := m.om.Oldest(); pair != nil; pair = pair.Next() {
+			if !yield(pair.Key, pair.Value) {
+				return
+			}
+		}
+	}
+}
+
+// ToMap converts to a regular Go map.
+// Note: The resulting map does not preserve order.
+func (m *Map[K, V]) ToMap() map[K]V {
+	if m == nil || m.om == nil {
+		return nil
+	}
+	result := make(map[K]V, m.om.Len())
+	for pair := m.om.Oldest(); pair != nil; pair = pair.Next() {
+		result[pair.Key] = pair.Value
+	}
+	return result
+}
+
+// MarshalJSON implements json.Marshaler. The JSON output preserves key order.
+func (m *Map[K, V]) MarshalJSON() ([]byte, error) {
+	if m == nil || m.om == nil {
+		return []byte("null"), nil
+	}
+	return json.Marshal(m.om)
+}
+
+// UnmarshalJSON implements json.Unmarshaler. The insertion order matches the
+// order of keys in the JSON input.
+func (m *Map[K, V]) UnmarshalJSON(data []byte) error {
+	m.om = orderedmap.New[K, V]()
+	return json.Unmarshal(data, &m.om)
+}

internal/orderedmap/orderedmap_test.go

@@ -0,0 +1,348 @@
+package orderedmap
+
+import (
+	"encoding/json"
+	"slices"
+	"testing"
+)
+
+func TestMap_BasicOperations(t *testing.T) {
+	m := New[string, int]()
+
+	// Test empty map
+	if m.Len() != 0 {
+		t.Errorf("expected Len() = 0, got %d", m.Len())
+	}
+	v, ok := m.Get("a")
+	if ok {
+		t.Error("expected Get on empty map to return false")
+	}
+	if v != 0 {
+		t.Errorf("expected zero value, got %d", v)
+	}
+
+	// Test Set and Get
+	m.Set("a", 1)
+	m.Set("b", 2)
+	m.Set("c", 3)
+
+	if m.Len() != 3 {
+		t.Errorf("expected Len() = 3, got %d", m.Len())
+	}
+
+	v, ok = m.Get("a")
+	if !ok || v != 1 {
+		t.Errorf("expected Get(a) = (1, true), got (%d, %v)", v, ok)
+	}
+
+	v, ok = m.Get("b")
+	if !ok || v != 2 {
+		t.Errorf("expected Get(b) = (2, true), got (%d, %v)", v, ok)
+	}
+
+	v, ok = m.Get("c")
+	if !ok || v != 3 {
+		t.Errorf("expected Get(c) = (3, true), got (%d, %v)", v, ok)
+	}
+
+	// Test updating existing key preserves position
+	m.Set("a", 10)
+	v, ok = m.Get("a")
+	if !ok || v != 10 {
+		t.Errorf("expected Get(a) = (10, true), got (%d, %v)", v, ok)
+	}
+	if m.Len() != 3 {
+		t.Errorf("expected Len() = 3 after update, got %d", m.Len())
+	}
+}
+
+func TestMap_InsertionOrderPreserved(t *testing.T) {
+	m := New[string, int]()
+
+	// Insert in non-alphabetical order
+	m.Set("z", 1)
+	m.Set("a", 2)
+	m.Set("m", 3)
+	m.Set("b", 4)
+
+	// Verify iteration order matches insertion order
+	var keys []string
+	var values []int
+	for k, v := range m.All() {
+		keys = append(keys, k)
+		values = append(values, v)
+	}
+
+	expectedKeys := []string{"z", "a", "m", "b"}
+	expectedValues := []int{1, 2, 3, 4}
+
+	if !slices.Equal(keys, expectedKeys) {
+		t.Errorf("expected keys %v, got %v", expectedKeys, keys)
+	}
+	if !slices.Equal(values, expectedValues) {
+		t.Errorf("expected values %v, got %v", expectedValues, values)
+	}
+}
+
+func TestMap_UpdatePreservesPosition(t *testing.T) {
+	m := New[string, int]()
+
+	m.Set("first", 1)
+	m.Set("second", 2)
+	m.Set("third", 3)
+
+	// Update middle element
+	m.Set("second", 20)
+
+	var keys []string
+	for k := range m.All() {
+		keys = append(keys, k)
+	}
+
+	// Order should still be first, second, third
+	expected := []string{"first", "second", "third"}
+	if !slices.Equal(keys, expected) {
+		t.Errorf("expected keys %v, got %v", expected, keys)
+	}
+}
+
+func TestMap_MarshalJSON_PreservesOrder(t *testing.T) {
+	m := New[string, int]()
+
+	// Insert in non-alphabetical order
+	m.Set("z", 1)
+	m.Set("a", 2)
+	m.Set("m", 3)
+
+	data, err := json.Marshal(m)
+	if err != nil {
+		t.Fatalf("Marshal failed: %v", err)
+	}
+
+	// JSON should preserve insertion order, not alphabetical
+	expected := `{"z":1,"a":2,"m":3}`
+	if string(data) != expected {
+		t.Errorf("expected %s, got %s", expected, string(data))
+	}
+}
+
+func TestMap_UnmarshalJSON_PreservesOrder(t *testing.T) {
+	// JSON with non-alphabetical key order
+	jsonData := `{"z":1,"a":2,"m":3}`
+
+	m := New[string, int]()
+	if err := json.Unmarshal([]byte(jsonData), m); err != nil {
+		t.Fatalf("Unmarshal failed: %v", err)
+	}
+
+	// Verify iteration order matches JSON order
+	var keys []string
+	for k := range m.All() {
+		keys = append(keys, k)
+	}
+
+	expected := []string{"z", "a", "m"}
+	if !slices.Equal(keys, expected) {
+		t.Errorf("expected keys %v, got %v", expected, keys)
+	}
+}
+
+func TestMap_JSONRoundTrip(t *testing.T) {
+	// Test that unmarshal -> marshal produces identical JSON
+	original := `{"zebra":"z","apple":"a","mango":"m","banana":"b"}`
+
+	m := New[string, string]()
+	if err := json.Unmarshal([]byte(original), m); err != nil {
+		t.Fatalf("Unmarshal failed: %v", err)
+	}
+
+	data, err := json.Marshal(m)
+	if err != nil {
+		t.Fatalf("Marshal failed: %v", err)
+	}
+
+	if string(data) != original {
+		t.Errorf("round trip failed: expected %s, got %s", original, string(data))
+	}
+}
+
+func TestMap_ToMap(t *testing.T) {
+	m := New[string, int]()
+	m.Set("a", 1)
+	m.Set("b", 2)
+
+	regular := m.ToMap()
+
+	if len(regular) != 2 {
+		t.Errorf("expected len 2, got %d", len(regular))
+	}
+	if regular["a"] != 1 {
+		t.Errorf("expected regular[a] = 1, got %d", regular["a"])
+	}
+	if regular["b"] != 2 {
+		t.Errorf("expected regular[b] = 2, got %d", regular["b"])
+	}
+}
+
+func TestMap_NilSafety(t *testing.T) {
+	var m *Map[string, int]
+
+	// All operations should be safe on nil
+	if m.Len() != 0 {
+		t.Errorf("expected Len() = 0 on nil map, got %d", m.Len())
+	}
+
+	v, ok := m.Get("a")
+	if ok {
+		t.Error("expected Get on nil map to return false")
+	}
+	if v != 0 {
+		t.Errorf("expected zero value from nil map, got %d", v)
+	}
+
+	// Set on nil is a no-op
+	m.Set("a", 1)
+	if m.Len() != 0 {
+		t.Errorf("expected Len() = 0 after Set on nil, got %d", m.Len())
+	}
+
+	// All returns empty iterator
+	var keys []string
+	for k := range m.All() {
+		keys = append(keys, k)
+	}
+	if len(keys) != 0 {
+		t.Errorf("expected empty iteration on nil map, got %v", keys)
+	}
+
+	// ToMap returns nil
+	if m.ToMap() != nil {
+		t.Error("expected ToMap to return nil on nil map")
+	}
+
+	// MarshalJSON returns null
+	data, err := json.Marshal(m)
+	if err != nil {
+		t.Fatalf("Marshal failed: %v", err)
+	}
+	if string(data) != "null" {
+		t.Errorf("expected null, got %s", string(data))
+	}
+}
+
+func TestMap_EmptyMapMarshal(t *testing.T) {
+	m := New[string, int]()
+
+	data, err := json.Marshal(m)
+	if err != nil {
+		t.Fatalf("Marshal failed: %v", err)
+	}
+	if string(data) != "{}" {
+		t.Errorf("expected {}, got %s", string(data))
+	}
+}
+
+func TestMap_NestedValues(t *testing.T) {
+	m := New[string, any]()
+	m.Set("string", "hello")
+	m.Set("number", 42)
+	m.Set("bool", true)
+	m.Set("nested", map[string]int{"x": 1})
+
+	data, err := json.Marshal(m)
+	if err != nil {
+		t.Fatalf("Marshal failed: %v", err)
+	}
+
+	expected := `{"string":"hello","number":42,"bool":true,"nested":{"x":1}}`
+	if string(data) != expected {
+		t.Errorf("expected %s, got %s", expected, string(data))
+	}
+}
+
+func TestMap_AllIteratorEarlyExit(t *testing.T) {
+	m := New[string, int]()
+	m.Set("a", 1)
+	m.Set("b", 2)
+	m.Set("c", 3)
+	m.Set("d", 4)
+
+	// Collect only first 2
+	var keys []string
+	for k := range m.All() {
+		keys = append(keys, k)
+		if len(keys) == 2 {
+			break
+		}
+	}
+
+	expected := []string{"a", "b"}
+	if !slices.Equal(keys, expected) {
+		t.Errorf("expected %v, got %v", expected, keys)
+	}
+}
+
+func TestMap_IntegerKeys(t *testing.T) {
+	m := New[int, string]()
+	m.Set(3, "three")
+	m.Set(1, "one")
+	m.Set(2, "two")
+
+	var keys []int
+	for k := range m.All() {
+		keys = append(keys, k)
+	}
+
+	// Should preserve insertion order, not numerical order
+	expected := []int{3, 1, 2}
+	if !slices.Equal(keys, expected) {
+		t.Errorf("expected %v, got %v", expected, keys)
+	}
+}
+
+func TestMap_UnmarshalIntoExisting(t *testing.T) {
+	m := New[string, int]()
+	m.Set("existing", 999)
+
+	// Unmarshal should replace contents
+	if err := json.Unmarshal([]byte(`{"new":1}`), m); err != nil {
+		t.Fatalf("Unmarshal failed: %v", err)
+	}
+
+	_, ok := m.Get("existing")
+	if ok {
+		t.Error("existing key should be gone after unmarshal")
+	}
+
+	v, ok := m.Get("new")
+	if !ok || v != 1 {
+		t.Errorf("expected Get(new) = (1, true), got (%d, %v)", v, ok)
+	}
+}
+
+func TestMap_LargeOrderPreservation(t *testing.T) {
+	m := New[string, int]()
+
+	// Create many keys in specific order
+	keys := make([]string, 100)
+	for i := range 100 {
+		keys[i] = string(rune('a' + (99 - i))) // reverse order: 'd', 'c', 'b', 'a' (extended)
+		if i >= 26 {
+			keys[i] = string(rune('A'+i-26)) + string(rune('a'+i%26))
+		}
+	}
+
+	for i, k := range keys {
+		m.Set(k, i)
+	}
+
+	// Verify order preserved
+	var resultKeys []string
+	for k := range m.All() {
+		resultKeys = append(resultKeys, k)
+	}
+
+	if !slices.Equal(keys, resultKeys) {
+		t.Error("large map should preserve insertion order")
+	}
+}

middleware/openai_test.go

@@ -19,6 +19,40 @@ import (
 	"github.com/ollama/ollama/openai"
 )
 
+// testPropsMap creates a ToolPropertiesMap from a map (convenience function for tests)
+func testPropsMap(m map[string]api.ToolProperty) *api.ToolPropertiesMap {
+	props := api.NewToolPropertiesMap()
+	for k, v := range m {
+		props.Set(k, v)
+	}
+	return props
+}
+
+// testArgs creates ToolCallFunctionArguments from a map (convenience function for tests)
+func testArgs(m map[string]any) api.ToolCallFunctionArguments {
+	args := api.NewToolCallFunctionArguments()
+	for k, v := range m {
+		args.Set(k, v)
+	}
+	return args
+}
+
+// argsComparer provides cmp options for comparing ToolCallFunctionArguments by value
+var argsComparer = cmp.Comparer(func(a, b api.ToolCallFunctionArguments) bool {
+	return cmp.Equal(a.ToMap(), b.ToMap())
+})
+
+// propsComparer provides cmp options for comparing ToolPropertiesMap by value
+var propsComparer = cmp.Comparer(func(a, b *api.ToolPropertiesMap) bool {
+	if a == nil && b == nil {
+		return true
+	}
+	if a == nil || b == nil {
+		return false
+	}
+	return cmp.Equal(a.ToMap(), b.ToMap())
+})
+
 const (
 	prefix = `data:image/jpeg;base64,`
 	image  = `iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR42mNk+A8AAQUBAScY42YAAAAASUVORK5CYII=`
@@ -221,10 +255,10 @@ func TestChatMiddleware(t *testing.T) {
 								ID: "id",
 								Function: api.ToolCallFunction{
 									Name: "get_current_weather",
-									Arguments: map[string]any{
+									Arguments: testArgs(map[string]any{
 										"location": "Paris, France",
 										"format":   "celsius",
-									},
+									}),
 								},
 							},
 						},
@@ -261,10 +295,10 @@ func TestChatMiddleware(t *testing.T) {
 								ID: "id",
 								Function: api.ToolCallFunction{
 									Name: "get_current_weather",
-									Arguments: map[string]any{
+									Arguments: testArgs(map[string]any{
 										"location": "Paris, France",
 										"format":   "celsius",
-									},
+									}),
 								},
 							},
 						},
@@ -300,10 +334,10 @@ func TestChatMiddleware(t *testing.T) {
 								ID: "id",
 								Function: api.ToolCallFunction{
 									Name: "get_current_weather",
-									Arguments: map[string]any{
+									Arguments: testArgs(map[string]any{
 										"location": "Paris, France",
 										"format":   "celsius",
-									},
+									}),
 								},
 							},
 						},
@@ -340,10 +374,10 @@ func TestChatMiddleware(t *testing.T) {
 								ID: "id",
 								Function: api.ToolCallFunction{
 									Name: "get_current_weather",
-									Arguments: map[string]any{
+									Arguments: testArgs(map[string]any{
 										"location": "Paris, France",
 										"format":   "celsius",
-									},
+									}),
 								},
 							},
 						},
@@ -380,10 +414,10 @@ func TestChatMiddleware(t *testing.T) {
 								ID: "id_abc",
 								Function: api.ToolCallFunction{
 									Name: "get_current_weather",
-									Arguments: map[string]any{
+									Arguments: testArgs(map[string]any{
 										"location": "Paris, France",
 										"format":   "celsius",
-									},
+									}),
 								},
 							},
 						},
@@ -426,10 +460,10 @@ func TestChatMiddleware(t *testing.T) {
 								ID: "id",
 								Function: api.ToolCallFunction{
 									Name: "get_current_weather",
-									Arguments: map[string]any{
+									Arguments: testArgs(map[string]any{
 										"location": "Paris, France",
 										"format":   "celsius",
-									},
+									}),
 								},
 							},
 						},
@@ -494,7 +528,7 @@ func TestChatMiddleware(t *testing.T) {
 							Parameters: api.ToolFunctionParameters{
 								Type:     "object",
 								Required: []string{"location"},
-								Properties: map[string]api.ToolProperty{
+								Properties: testPropsMap(map[string]api.ToolProperty{
 									"location": {
 										Type:        api.PropertyType{"string"},
 										Description: "The city and state",
@@ -503,7 +537,7 @@ func TestChatMiddleware(t *testing.T) {
 										Type: api.PropertyType{"string"},
 										Enum: []any{"celsius", "fahrenheit"},
 									},
-								},
+								}),
 							},
 						},
 					},
@@ -558,7 +592,7 @@ func TestChatMiddleware(t *testing.T) {
 				}
 				return
 			}
-			if diff := cmp.Diff(&tc.req, capturedRequest); diff != "" {
+			if diff := cmp.Diff(&tc.req, capturedRequest, argsComparer, propsComparer); diff != "" {
 				t.Fatalf("requests did not match: %+v", diff)
 			}
 			if diff := cmp.Diff(tc.err, errResp); diff != "" {

model/parsers/cogito_test.go

@@ -40,9 +40,9 @@ func TestCogitoParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "get_weather",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"location": "Paris",
-						},
+						}),
 					},
 				},
 			},
@@ -52,9 +52,9 @@ func TestCogitoParser(t *testing.T) {
 					Function: api.ToolFunction{
 						Name: "get_weather",
 						Parameters: api.ToolFunctionParameters{
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"location": {Type: api.PropertyType{"string"}},
-							},
+							}),
 						},
 					},
 				},
@@ -71,9 +71,9 @@ func TestCogitoParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "get_weather",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"location": "Paris",
-						},
+						}),
 					},
 				},
 			},
@@ -83,9 +83,9 @@ func TestCogitoParser(t *testing.T) {
 					Function: api.ToolFunction{
 						Name: "get_weather",
 						Parameters: api.ToolFunctionParameters{
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"location": {Type: api.PropertyType{"string"}},
-							},
+							}),
 						},
 					},
 				},
@@ -103,17 +103,17 @@ func TestCogitoParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "get_weather",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"location": "Paris",
-						},
+						}),
 					},
 				},
 				{
 					Function: api.ToolCallFunction{
 						Name: "get_weather",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"location": "London",
-						},
+						}),
 					},
 				},
 			},
@@ -123,9 +123,9 @@ func TestCogitoParser(t *testing.T) {
 					Function: api.ToolFunction{
 						Name: "get_weather",
 						Parameters: api.ToolFunctionParameters{
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"location": {Type: api.PropertyType{"string"}},
-							},
+							}),
 						},
 					},
 				},
@@ -140,11 +140,11 @@ func TestCogitoParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "process_data",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"items":  []any{"item1", "item2"},
 							"config": map[string]any{"enabled": true, "threshold": 0.95},
 							"count":  42.0,
-						},
+						}),
 					},
 				},
 			},
@@ -238,7 +238,7 @@ This is line 3</think>Final response here.`,
 				t.Errorf("thinking mismatch (-want +got):\n%s", diff)
 			}
 
-			if diff := cmp.Diff(tt.expectedToolCalls, toolCalls); diff != "" {
+			if diff := cmp.Diff(tt.expectedToolCalls, toolCalls, argsComparer); diff != "" {
 				t.Errorf("tool calls mismatch (-want +got):\n%s", diff)
 			}
 		})
@@ -277,9 +277,9 @@ func TestCogitoParser_Streaming(t *testing.T) {
 		{
 			Function: api.ToolCallFunction{
 				Name: "test_tool",
-				Arguments: api.ToolCallFunctionArguments{
+				Arguments: testArgs(map[string]any{
 					"arg": "value",
-				},
+				}),
 			},
 		},
 	}
@@ -292,7 +292,7 @@ func TestCogitoParser_Streaming(t *testing.T) {
 		t.Errorf("expected thinking %q, got %q", expectedThinking, finalThinking.String())
 	}
 
-	if diff := cmp.Diff(expectedToolCalls, finalToolCalls); diff != "" {
+	if diff := cmp.Diff(expectedToolCalls, finalToolCalls, argsComparer); diff != "" {
 		t.Errorf("tool calls mismatch (-want +got):\n%s", diff)
 	}
 }
@@ -367,7 +367,7 @@ func TestCogitoParser_StreamingEdgeCases(t *testing.T) {
 				t.Errorf("expected thinking %q, got %q", tt.expectedThinking, finalThinking.String())
 			}
 
-			if diff := cmp.Diff(tt.expectedToolCalls, finalToolCalls); diff != "" {
+			if diff := cmp.Diff(tt.expectedToolCalls, finalToolCalls, argsComparer); diff != "" {
 				t.Errorf("tool calls mismatch (-want +got):\n%s", diff)
 			}
 		})
@@ -412,9 +412,9 @@ func TestCogitoParser_parseToolCallContent(t *testing.T) {
 			expected: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "get_weather",
-					Arguments: api.ToolCallFunctionArguments{
+					Arguments: testArgs(map[string]any{
 						"location": "Paris",
-					},
+					}),
 				},
 			},
 			expectError: false,
@@ -427,11 +427,11 @@ func TestCogitoParser_parseToolCallContent(t *testing.T) {
 			expected: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "process_data",
-					Arguments: api.ToolCallFunctionArguments{
+					Arguments: testArgs(map[string]any{
 						"items":  []any{"item1", "item2"},
 						"config": map[string]any{"enabled": true},
 						"count":  42.0,
-					},
+					}),
 				},
 			},
 			expectError: false,
@@ -444,7 +444,7 @@ func TestCogitoParser_parseToolCallContent(t *testing.T) {
 			expected: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name:      "no_args_tool",
-					Arguments: api.ToolCallFunctionArguments{},
+					Arguments: api.NewToolCallFunctionArguments(),
 				},
 			},
 			expectError: false,
@@ -493,9 +493,9 @@ func TestCogitoParser_parseToolCallContent(t *testing.T) {
 			expected: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "get_weather",
-					Arguments: api.ToolCallFunctionArguments{
+					Arguments: testArgs(map[string]any{
 						"location": "Paris",
-					},
+					}),
 				},
 			},
 			expectError: false,
@@ -511,10 +511,10 @@ func TestCogitoParser_parseToolCallContent(t *testing.T) {
 			expected: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "get_weather",
-					Arguments: api.ToolCallFunctionArguments{
+					Arguments: testArgs(map[string]any{
 						"location": "Paris",
 						"units":    "metric",
-					},
+					}),
 				},
 			},
 			expectError: false,
@@ -527,13 +527,13 @@ func TestCogitoParser_parseToolCallContent(t *testing.T) {
 			expected: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "complex_tool",
-					Arguments: api.ToolCallFunctionArguments{
+					Arguments: testArgs(map[string]any{
 						"nested": map[string]any{
 							"deep": map[string]any{
 								"value": 123.0,
 							},
 						},
-					},
+					}),
 				},
 			},
 			expectError: false,
@@ -557,7 +557,7 @@ func TestCogitoParser_parseToolCallContent(t *testing.T) {
 				t.Fatalf("unexpected error: %v", err)
 			}
 
-			if diff := cmp.Diff(tt.expected, result); diff != "" {
+			if diff := cmp.Diff(tt.expected, result, argsComparer); diff != "" {
 				t.Errorf("tool call mismatch (-want +got):\n%s", diff)
 			}
 		})

model/parsers/deepseek3_test.go

@@ -51,9 +51,9 @@ func TestDeepSeekParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "get_weather",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"location": "Paris",
-						},
+						}),
 					},
 				},
 			},
@@ -67,17 +67,17 @@ func TestDeepSeekParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "get_weather",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"location": "Paris",
-						},
+						}),
 					},
 				},
 				{
 					Function: api.ToolCallFunction{
 						Name: "get_weather",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"location": "London",
-						},
+						}),
 					},
 				},
 			},
@@ -97,10 +97,10 @@ func TestDeepSeekParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "process_data",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"items":  []interface{}{"item1", "item2"},
 							"config": map[string]interface{}{"enabled": true, "threshold": 0.95},
-						},
+						}),
 					},
 				},
 			},
@@ -115,9 +115,9 @@ func TestDeepSeekParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "get_weather",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"location": "Paris",
-						},
+						}),
 					},
 				},
 			},
@@ -162,9 +162,9 @@ func TestDeepSeekParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "get_weather",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"location": "Tokyo",
-						},
+						}),
 					},
 				},
 			},
@@ -191,10 +191,10 @@ func TestDeepSeekParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "search",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"query":    "北京天气",
 							"language": "中文",
-						},
+						}),
 					},
 				},
 			},
@@ -220,10 +220,10 @@ func TestDeepSeekParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "execute_command",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"command": "ls && echo \"done\"",
 							"path":    "/home/user",
-						},
+						}),
 					},
 				},
 			},
@@ -244,7 +244,7 @@ func TestDeepSeekParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "ping",
-						Arguments: api.ToolCallFunctionArguments{},
+						Arguments: api.NewToolCallFunctionArguments(),
 					},
 				},
 			},
@@ -276,7 +276,7 @@ func TestDeepSeekParser(t *testing.T) {
 				t.Errorf("Thinking mismatch (-want +got):\n%s", diff)
 			}
 
-			if diff := cmp.Diff(tt.expectedCalls, calls); diff != "" {
+			if diff := cmp.Diff(tt.expectedCalls, calls, argsComparer); diff != "" {
 				t.Errorf("Tool calls mismatch (-want +got):\n%s", diff)
 			}
 		})
@@ -313,9 +313,9 @@ func TestDeepSeekParser_Streaming(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "get_weather",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"location": "Paris",
-						},
+						}),
 					},
 				},
 			},
@@ -342,7 +342,7 @@ func TestDeepSeekParser_Streaming(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "test",
-						Arguments: api.ToolCallFunctionArguments{},
+						Arguments: api.NewToolCallFunctionArguments(),
 					},
 				},
 			},
@@ -375,10 +375,10 @@ func TestDeepSeekParser_Streaming(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "calc",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"x": float64(42),
 							"y": float64(24),
-						},
+						}),
 					},
 				},
 			},
@@ -414,7 +414,7 @@ func TestDeepSeekParser_Streaming(t *testing.T) {
 				t.Errorf("Thinking mismatch (-want +got):\n%s", diff)
 			}
 
-			if diff := cmp.Diff(tt.expectedCalls, allCalls); diff != "" {
+			if diff := cmp.Diff(tt.expectedCalls, allCalls, argsComparer); diff != "" {
 				t.Errorf("Tool calls mismatch (-want +got):\n%s", diff)
 			}
 		})
@@ -469,7 +469,7 @@ func TestDeepSeekParser_Init(t *testing.T) {
 
 	returnedTools := parser.Init(tools, nil, &api.ThinkValue{Value: true})
 
-	if diff := cmp.Diff(tools, returnedTools); diff != "" {
+	if diff := cmp.Diff(tools, returnedTools, toolsComparer); diff != "" {
 		t.Errorf("Init() returned tools mismatch (-want +got):\n%s", diff)
 	}
 
@@ -492,9 +492,9 @@ func TestDeepSeek3Parser_parseToolCallContent(t *testing.T) {
 			expected: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "get_weather",
-					Arguments: api.ToolCallFunctionArguments{
+					Arguments: testArgs(map[string]any{
 						"location": "Paris",
-					},
+					}),
 				},
 			},
 		},
@@ -504,10 +504,10 @@ func TestDeepSeek3Parser_parseToolCallContent(t *testing.T) {
 			expected: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "process_data",
-					Arguments: api.ToolCallFunctionArguments{
+					Arguments: testArgs(map[string]any{
 						"items":  []interface{}{"a", "b"},
 						"config": map[string]interface{}{"enabled": true},
-					},
+					}),
 				},
 			},
 		},
@@ -517,7 +517,7 @@ func TestDeepSeek3Parser_parseToolCallContent(t *testing.T) {
 			expected: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name:      "ping",
-					Arguments: api.ToolCallFunctionArguments{},
+					Arguments: api.NewToolCallFunctionArguments(),
 				},
 			},
 		},
@@ -527,9 +527,9 @@ func TestDeepSeek3Parser_parseToolCallContent(t *testing.T) {
 			expected: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "获取天气",
-					Arguments: api.ToolCallFunctionArguments{
+					Arguments: testArgs(map[string]any{
 						"城市": "北京",
-					},
+					}),
 				},
 			},
 		},
@@ -539,10 +539,10 @@ func TestDeepSeek3Parser_parseToolCallContent(t *testing.T) {
 			expected: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "execute",
-					Arguments: api.ToolCallFunctionArguments{
+					Arguments: testArgs(map[string]any{
 						"command": "ls && echo \"done\"",
 						"path":    "/home/user",
-					},
+					}),
 				},
 			},
 		},
@@ -552,11 +552,11 @@ func TestDeepSeek3Parser_parseToolCallContent(t *testing.T) {
 			expected: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "calculate",
-					Arguments: api.ToolCallFunctionArguments{
+					Arguments: testArgs(map[string]any{
 						"x":       3.14,
 						"y":       float64(42),
 						"enabled": true,
-					},
+					}),
 				},
 			},
 		},
@@ -577,9 +577,9 @@ func TestDeepSeek3Parser_parseToolCallContent(t *testing.T) {
 			expected: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "",
-					Arguments: api.ToolCallFunctionArguments{
+					Arguments: testArgs(map[string]any{
 						"arg": "value",
-					},
+					}),
 				},
 			},
 		},
@@ -606,7 +606,7 @@ func TestDeepSeek3Parser_parseToolCallContent(t *testing.T) {
 				t.Fatalf("Unexpected error: %v", err)
 			}
 
-			if diff := cmp.Diff(tt.expected, result); diff != "" {
+			if diff := cmp.Diff(tt.expected, result, argsComparer); diff != "" {
 				t.Errorf("parseToolCallContent() mismatch (-want +got):\n%s", diff)
 			}
 		})

model/parsers/functiongemma.go

@@ -166,7 +166,7 @@ func (p *FunctionGemmaParser) parseToolCall(content string) (api.ToolCall, error
 
 // parseArguments parses the key:value,key:value format
 func (p *FunctionGemmaParser) parseArguments(argsStr string) api.ToolCallFunctionArguments {
-	args := make(api.ToolCallFunctionArguments)
+	args := api.NewToolCallFunctionArguments()
 	if argsStr == "" {
 		return args
 	}
@@ -185,7 +185,7 @@ func (p *FunctionGemmaParser) parseArguments(argsStr string) api.ToolCallFunctio
 		value := part[colonIdx+1:]
 
 		// Parse the value
-		args[key] = p.parseValue(value)
+		args.Set(key, p.parseValue(value))
 	}
 
 	return args

model/parsers/functiongemma_test.go

@@ -3,6 +3,7 @@ package parsers
 import (
 	"testing"
 
+	"github.com/google/go-cmp/cmp"
 	"github.com/ollama/ollama/api"
 	"github.com/stretchr/testify/assert"
 )
@@ -36,9 +37,9 @@ func TestFunctionGemmaParser(t *testing.T) {
 						Name: "get_weather",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"city": {Type: api.PropertyType{"string"}},
-							},
+							}),
 						},
 					},
 				},
@@ -47,7 +48,7 @@ func TestFunctionGemmaParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: api.ToolCallFunctionArguments{"city": "Paris"},
+						Arguments: testArgs(map[string]any{"city": "Paris"}),
 					},
 				},
 			},
@@ -66,7 +67,7 @@ func TestFunctionGemmaParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: api.ToolCallFunctionArguments{"city": "Paris"},
+						Arguments: testArgs(map[string]any{"city": "Paris"}),
 					},
 				},
 			},
@@ -84,7 +85,7 @@ func TestFunctionGemmaParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "add",
-						Arguments: api.ToolCallFunctionArguments{"a": int64(1), "b": int64(2)},
+						Arguments: testArgs(map[string]any{"a": int64(1), "b": int64(2)}),
 					},
 				},
 			},
@@ -102,7 +103,7 @@ func TestFunctionGemmaParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "set_flag",
-						Arguments: api.ToolCallFunctionArguments{"enabled": true, "verbose": false},
+						Arguments: testArgs(map[string]any{"enabled": true, "verbose": false}),
 					},
 				},
 			},
@@ -124,13 +125,13 @@ func TestFunctionGemmaParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: api.ToolCallFunctionArguments{"city": "Paris"},
+						Arguments: testArgs(map[string]any{"city": "Paris"}),
 					},
 				},
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: api.ToolCallFunctionArguments{"city": "London"},
+						Arguments: testArgs(map[string]any{"city": "London"}),
 					},
 				},
 			},
@@ -152,7 +153,7 @@ func TestFunctionGemmaParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "process",
-						Arguments: api.ToolCallFunctionArguments{"items": []any{"a", "b", "c"}},
+						Arguments: testArgs(map[string]any{"items": []any{"a", "b", "c"}}),
 					},
 				},
 			},
@@ -173,9 +174,9 @@ func TestFunctionGemmaParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "update",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"data": map[string]any{"name": "test", "value": int64(42)},
-						},
+						}),
 					},
 				},
 			},
@@ -198,7 +199,7 @@ func TestFunctionGemmaParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_time",
-						Arguments: api.ToolCallFunctionArguments{},
+						Arguments: api.NewToolCallFunctionArguments(),
 					},
 				},
 			},
@@ -224,7 +225,7 @@ func TestFunctionGemmaParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "set_temp",
-						Arguments: api.ToolCallFunctionArguments{"value": 3.14},
+						Arguments: testArgs(map[string]any{"value": 3.14}),
 					},
 				},
 			},
@@ -242,7 +243,7 @@ func TestFunctionGemmaParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "test",
-						Arguments: api.ToolCallFunctionArguments{},
+						Arguments: api.NewToolCallFunctionArguments(),
 					},
 				},
 			},
@@ -261,7 +262,7 @@ func TestFunctionGemmaParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "greet",
-						Arguments: api.ToolCallFunctionArguments{"name": "日本語"},
+						Arguments: testArgs(map[string]any{"name": "日本語"}),
 					},
 				},
 			},
@@ -281,11 +282,11 @@ func TestFunctionGemmaParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "search",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"query":  "test",
 							"limit":  int64(10),
 							"offset": int64(0),
-						},
+						}),
 					},
 				},
 			},
@@ -308,14 +309,14 @@ func TestFunctionGemmaParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "create",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"config": map[string]any{
 								"settings": map[string]any{
 									"enabled": true,
 									"name":    "test",
 								},
 							},
-						},
+						}),
 					},
 				},
 			},
@@ -345,13 +346,13 @@ func TestFunctionGemmaParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: api.ToolCallFunctionArguments{"city": "Paris"},
+						Arguments: testArgs(map[string]any{"city": "Paris"}),
 					},
 				},
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_time",
-						Arguments: api.ToolCallFunctionArguments{"timezone": "UTC"},
+						Arguments: testArgs(map[string]any{"timezone": "UTC"}),
 					},
 				},
 			},
@@ -372,13 +373,13 @@ func TestFunctionGemmaParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "first",
-						Arguments: api.ToolCallFunctionArguments{},
+						Arguments: api.NewToolCallFunctionArguments(),
 					},
 				},
 				{
 					Function: api.ToolCallFunction{
 						Name:      "second",
-						Arguments: api.ToolCallFunctionArguments{},
+						Arguments: api.NewToolCallFunctionArguments(),
 					},
 				},
 			},
@@ -411,7 +412,9 @@ func TestFunctionGemmaParser(t *testing.T) {
 			}
 
 			assert.Equal(t, tt.expectedText, allContent)
-			assert.Equal(t, tt.expectedCalls, allCalls)
+			if diff := cmp.Diff(tt.expectedCalls, allCalls, argsComparer); diff != "" {
+				t.Errorf("calls mismatch (-want +got):\n%s", diff)
+			}
 		})
 	}
 }

model/parsers/ministral.go

@@ -112,8 +112,8 @@ func (p *MinistralParser) Add(s string, done bool) (content string, thinking str
 			before, _ := splitAtTag(&p.buffer, "}", false)
 			before += "}"
 
-			var data map[string]any
+			var args api.ToolCallFunctionArguments
-			if err := json.Unmarshal([]byte(before), &data); err != nil {
+			if err := json.Unmarshal([]byte(before), &args); err != nil {
 				// todo - throw a better error
 				return "", "", calls, err
 			}
@@ -123,7 +123,7 @@ func (p *MinistralParser) Add(s string, done bool) (content string, thinking str
 			call := api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name:      p.currentTool.Function.Name,
-					Arguments: api.ToolCallFunctionArguments(data),
+					Arguments: args,
 				},
 			}
 			calls = append(calls, call)

model/parsers/nemotron3nano.go

@@ -225,7 +225,7 @@ func (p *Nemotron3NanoParser) parseToolCall(content string) (api.ToolCall, error
 	toolCall.Function.Name = fnMatch[1]
 
 	// Extract parameters
-	toolCall.Function.Arguments = make(api.ToolCallFunctionArguments)
+	toolCall.Function.Arguments = api.NewToolCallFunctionArguments()
 	paramMatches := nemotronParameterRegex.FindAllStringSubmatch(content, -1)
 	for _, match := range paramMatches {
 		if len(match) >= 3 {
@@ -233,7 +233,7 @@ func (p *Nemotron3NanoParser) parseToolCall(content string) (api.ToolCall, error
 			paramValue := strings.TrimSpace(match[2])
 
 			// Try to parse as typed value based on tool definition
-			toolCall.Function.Arguments[paramName] = p.parseParamValue(paramName, paramValue)
+			toolCall.Function.Arguments.Set(paramName, p.parseParamValue(paramName, paramValue))
 		}
 	}
 
@@ -244,9 +244,11 @@ func (p *Nemotron3NanoParser) parseParamValue(paramName string, raw string) any
 	// Find the matching tool to get parameter type
 	var paramType api.PropertyType
 	for _, tool := range p.tools {
-		if prop, ok := tool.Function.Parameters.Properties[paramName]; ok {
+		if tool.Function.Parameters.Properties != nil {
-			paramType = prop.Type
+			if prop, ok := tool.Function.Parameters.Properties.Get(paramName); ok {
-			break
+				paramType = prop.Type
+				break
+			}
 		}
 	}
 

model/parsers/nemotron3nano_test.go

@@ -51,7 +51,7 @@ func TestNemotron3NanoParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: map[string]any{"city": "Paris"},
+						Arguments: testArgs(map[string]any{"city": "Paris"}),
 					},
 				},
 			},
@@ -65,7 +65,7 @@ func TestNemotron3NanoParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: map[string]any{"city": "NYC"},
+						Arguments: testArgs(map[string]any{"city": "NYC"}),
 					},
 				},
 			},
@@ -78,10 +78,10 @@ func TestNemotron3NanoParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "book_flight",
-						Arguments: map[string]any{
+						Arguments: testArgs(map[string]any{
 							"from": "SFO",
 							"to":   "NYC",
-						},
+						}),
 					},
 				},
 			},
@@ -95,13 +95,13 @@ func TestNemotron3NanoParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: map[string]any{"city": "San Francisco"},
+						Arguments: testArgs(map[string]any{"city": "San Francisco"}),
 					},
 				},
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: map[string]any{"city": "New York"},
+						Arguments: testArgs(map[string]any{"city": "New York"}),
 					},
 				},
 			},
@@ -115,7 +115,7 @@ func TestNemotron3NanoParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: map[string]any{"city": "Paris"},
+						Arguments: testArgs(map[string]any{"city": "Paris"}),
 					},
 				},
 			},
@@ -130,7 +130,7 @@ func TestNemotron3NanoParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "search",
-						Arguments: map[string]any{"query": "test"},
+						Arguments: testArgs(map[string]any{"query": "test"}),
 					},
 				},
 			},
@@ -143,7 +143,7 @@ func TestNemotron3NanoParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "create_note",
-						Arguments: map[string]any{"content": "Line 1\nLine 2\nLine 3"},
+						Arguments: testArgs(map[string]any{"content": "Line 1\nLine 2\nLine 3"}),
 					},
 				},
 			},
@@ -165,7 +165,7 @@ func TestNemotron3NanoParser(t *testing.T) {
 			name:          "tool call with no function name - returns empty tool call",
 			input:         "<tool_call>\n<function=>\n</function>\n</tool_call>",
 			thinkValue:    nil,
-			expectedCalls: []api.ToolCall{{Function: api.ToolCallFunction{Name: "", Arguments: nil}}},
+			expectedCalls: []api.ToolCall{{Function: api.ToolCallFunction{Name: "", Arguments: api.NewToolCallFunctionArguments()}}},
 		},
 		{
 			name:            "content with newlines preserved",
@@ -194,7 +194,7 @@ func TestNemotron3NanoParser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "set_temp",
-						Arguments: map[string]any{"value": "42"},
+						Arguments: testArgs(map[string]any{"value": "42"}),
 					},
 				},
 			},
@@ -226,7 +226,7 @@ func TestNemotron3NanoParser(t *testing.T) {
 			if diff := cmp.Diff(thinking, tt.expectedThinking); diff != "" {
 				t.Errorf("thinking mismatch (-got +want):\n%s", diff)
 			}
-			if diff := cmp.Diff(calls, tt.expectedCalls); diff != "" {
+			if diff := cmp.Diff(calls, tt.expectedCalls, argsComparer); diff != "" {
 				t.Errorf("calls mismatch (-got +want):\n%s", diff)
 			}
 		})
@@ -276,7 +276,7 @@ func TestNemotron3NanoParser_Streaming(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: map[string]any{"city": "Paris"},
+						Arguments: testArgs(map[string]any{"city": "Paris"}),
 					},
 				},
 			},
@@ -290,7 +290,7 @@ func TestNemotron3NanoParser_Streaming(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: map[string]any{"city": "NYC"},
+						Arguments: testArgs(map[string]any{"city": "NYC"}),
 					},
 				},
 			},
@@ -302,7 +302,7 @@ func TestNemotron3NanoParser_Streaming(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "test",
-						Arguments: map[string]any{},
+						Arguments: api.NewToolCallFunctionArguments(),
 					},
 				},
 			},
@@ -329,10 +329,10 @@ func TestNemotron3NanoParser_Streaming(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "book_flight",
-						Arguments: map[string]any{
+						Arguments: testArgs(map[string]any{
 							"from": "SFO",
 							"to":   "NYC",
-						},
+						}),
 					},
 				},
 			},
@@ -347,7 +347,7 @@ func TestNemotron3NanoParser_Streaming(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "search",
-						Arguments: map[string]any{"query": "test query"},
+						Arguments: testArgs(map[string]any{"query": "test query"}),
 					},
 				},
 			},
@@ -367,13 +367,13 @@ func TestNemotron3NanoParser_Streaming(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: map[string]any{"city": "San Francisco"},
+						Arguments: testArgs(map[string]any{"city": "San Francisco"}),
 					},
 				},
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: map[string]any{"city": "New York"},
+						Arguments: testArgs(map[string]any{"city": "New York"}),
 					},
 				},
 			},
@@ -386,7 +386,7 @@ func TestNemotron3NanoParser_Streaming(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "create_note",
-						Arguments: map[string]any{"content": "Line 1\nLine 2\nLine 3"},
+						Arguments: testArgs(map[string]any{"content": "Line 1\nLine 2\nLine 3"}),
 					},
 				},
 			},
@@ -413,7 +413,7 @@ func TestNemotron3NanoParser_Streaming(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "test",
-						Arguments: map[string]any{},
+						Arguments: api.NewToolCallFunctionArguments(),
 					},
 				},
 			},
@@ -426,7 +426,7 @@ func TestNemotron3NanoParser_Streaming(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "test",
-						Arguments: map[string]any{"name": ""},
+						Arguments: testArgs(map[string]any{"name": ""}),
 					},
 				},
 			},
@@ -473,7 +473,7 @@ func TestNemotron3NanoParser_Streaming(t *testing.T) {
 			if diff := cmp.Diff(allThinking, tt.expectedThinking); diff != "" {
 				t.Errorf("thinking mismatch (-got +want):\n%s", diff)
 			}
-			if diff := cmp.Diff(allCalls, tt.expectedCalls); diff != "" {
+			if diff := cmp.Diff(allCalls, tt.expectedCalls, argsComparer); diff != "" {
 				t.Errorf("calls mismatch (-got +want):\n%s", diff)
 			}
 		})
@@ -537,9 +537,9 @@ func TestNemotron3NanoParser_WithTools(t *testing.T) {
 				Name: "get_weather",
 				Parameters: api.ToolFunctionParameters{
 					Type: "object",
-					Properties: map[string]api.ToolProperty{
+					Properties: testPropsMap(map[string]api.ToolProperty{
 						"city": {Type: api.PropertyType{"string"}},
-					},
+					}),
 				},
 			},
 		},
@@ -548,7 +548,7 @@ func TestNemotron3NanoParser_WithTools(t *testing.T) {
 	p := &Nemotron3NanoParser{}
 	returnedTools := p.Init(tools, nil, nil)
 
-	if diff := cmp.Diff(returnedTools, tools); diff != "" {
+	if diff := cmp.Diff(returnedTools, tools, toolsComparer); diff != "" {
 		t.Errorf("tools mismatch (-got +want):\n%s", diff)
 	}
 
@@ -563,12 +563,12 @@ func TestNemotron3NanoParser_WithTools(t *testing.T) {
 		{
 			Function: api.ToolCallFunction{
 				Name:      "get_weather",
-				Arguments: map[string]any{"city": "Paris"},
+				Arguments: testArgs(map[string]any{"city": "Paris"}),
 			},
 		},
 	}
 
-	if diff := cmp.Diff(calls, expectedCalls); diff != "" {
+	if diff := cmp.Diff(calls, expectedCalls, argsComparer); diff != "" {
 		t.Errorf("calls mismatch (-got +want):\n%s", diff)
 	}
 }

model/parsers/olmo3.go

@@ -242,8 +242,8 @@ func parseOlmo3SingleFunctionCall(s string) (api.ToolCall, error) {
 
 // parseOlmo3Arguments parses comma-separated key=value pairs
 // Handles nested parentheses, brackets, braces, and quoted strings
-func parseOlmo3Arguments(s string) (map[string]any, error) {
+func parseOlmo3Arguments(s string) (api.ToolCallFunctionArguments, error) {
-	args := make(map[string]any)
+	args := api.NewToolCallFunctionArguments()
 	s = strings.TrimSpace(s)
 	if s == "" {
 		return args, nil
@@ -261,7 +261,7 @@ func parseOlmo3Arguments(s string) (map[string]any, error) {
 		// Find the first = sign
 		eqIdx := strings.Index(part, "=")
 		if eqIdx == -1 {
-			return nil, fmt.Errorf("invalid argument format: %s", part)
+			return api.ToolCallFunctionArguments{}, fmt.Errorf("invalid argument format: %s", part)
 		}
 
 		key := strings.TrimSpace(part[:eqIdx])
@@ -269,10 +269,10 @@ func parseOlmo3Arguments(s string) (map[string]any, error) {
 
 		value, err := parseOlmo3Value(valueStr)
 		if err != nil {
-			return nil, fmt.Errorf("failed to parse value for %s: %w", key, err)
+			return api.ToolCallFunctionArguments{}, fmt.Errorf("failed to parse value for %s: %w", key, err)
 		}
 
-		args[key] = value
+		args.Set(key, value)
 	}
 
 	return args, nil

model/parsers/olmo3_test.go

@@ -28,7 +28,7 @@ func TestOlmo3Parser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: map[string]any{"location": "San Francisco"},
+						Arguments: testArgs(map[string]any{"location": "San Francisco"}),
 					},
 				},
 			},
@@ -41,7 +41,7 @@ func TestOlmo3Parser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: map[string]any{"location": "NYC"},
+						Arguments: testArgs(map[string]any{"location": "NYC"}),
 					},
 				},
 			},
@@ -53,11 +53,11 @@ func TestOlmo3Parser(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "book_flight",
-						Arguments: map[string]any{
+						Arguments: testArgs(map[string]any{
 							"from": "SFO",
 							"to":   "NYC",
 							"date": "2024-01-15",
-						},
+						}),
 					},
 				},
 			},
@@ -70,13 +70,13 @@ get_weather(location="New York")</function_calls>`,
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: map[string]any{"location": "San Francisco"},
+						Arguments: testArgs(map[string]any{"location": "San Francisco"}),
 					},
 				},
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: map[string]any{"location": "New York"},
+						Arguments: testArgs(map[string]any{"location": "New York"}),
 					},
 				},
 			},
@@ -88,7 +88,7 @@ get_weather(location="New York")</function_calls>`,
 				{
 					Function: api.ToolCallFunction{
 						Name:      "set_temperature",
-						Arguments: map[string]any{"value": int64(72)},
+						Arguments: testArgs(map[string]any{"value": int64(72)}),
 					},
 				},
 			},
@@ -100,7 +100,7 @@ get_weather(location="New York")</function_calls>`,
 				{
 					Function: api.ToolCallFunction{
 						Name:      "set_price",
-						Arguments: map[string]any{"amount": 19.99},
+						Arguments: testArgs(map[string]any{"amount": 19.99}),
 					},
 				},
 			},
@@ -112,7 +112,7 @@ get_weather(location="New York")</function_calls>`,
 				{
 					Function: api.ToolCallFunction{
 						Name:      "toggle_setting",
-						Arguments: map[string]any{"enabled": true},
+						Arguments: testArgs(map[string]any{"enabled": true}),
 					},
 				},
 			},
@@ -124,7 +124,7 @@ get_weather(location="New York")</function_calls>`,
 				{
 					Function: api.ToolCallFunction{
 						Name:      "clear_value",
-						Arguments: map[string]any{"field": nil},
+						Arguments: testArgs(map[string]any{"field": nil}),
 					},
 				},
 			},
@@ -136,7 +136,7 @@ get_weather(location="New York")</function_calls>`,
 				{
 					Function: api.ToolCallFunction{
 						Name:      "process_items",
-						Arguments: map[string]any{"items": []any{"apple", "banana", "cherry"}},
+						Arguments: testArgs(map[string]any{"items": []any{"apple", "banana", "cherry"}}),
 					},
 				},
 			},
@@ -148,12 +148,12 @@ get_weather(location="New York")</function_calls>`,
 				{
 					Function: api.ToolCallFunction{
 						Name: "update_config",
-						Arguments: map[string]any{
+						Arguments: testArgs(map[string]any{
 							"settings": map[string]any{
 								"theme":    "dark",
 								"fontSize": int64(14),
 							},
-						},
+						}),
 					},
 				},
 			},
@@ -165,7 +165,7 @@ get_weather(location="New York")</function_calls>`,
 				{
 					Function: api.ToolCallFunction{
 						Name: "create_request",
-						Arguments: map[string]any{
+						Arguments: testArgs(map[string]any{
 							"data": map[string]any{
 								"user": map[string]any{
 									"name": "John",
@@ -173,7 +173,7 @@ get_weather(location="New York")</function_calls>`,
 								},
 								"active": true,
 							},
-						},
+						}),
 					},
 				},
 			},
@@ -185,7 +185,7 @@ get_weather(location="New York")</function_calls>`,
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_current_time",
-						Arguments: map[string]any{},
+						Arguments: testArgs(map[string]any{}),
 					},
 				},
 			},
@@ -197,7 +197,7 @@ get_weather(location="New York")</function_calls>`,
 				{
 					Function: api.ToolCallFunction{
 						Name:      "search",
-						Arguments: map[string]any{"query": "hello world"},
+						Arguments: testArgs(map[string]any{"query": "hello world"}),
 					},
 				},
 			},
@@ -209,7 +209,7 @@ get_weather(location="New York")</function_calls>`,
 				{
 					Function: api.ToolCallFunction{
 						Name:      "search",
-						Arguments: map[string]any{"query": `say "hello"`},
+						Arguments: testArgs(map[string]any{"query": `say "hello"`}),
 					},
 				},
 			},
@@ -221,11 +221,11 @@ get_weather(location="New York")</function_calls>`,
 				{
 					Function: api.ToolCallFunction{
 						Name: "create_user",
-						Arguments: map[string]any{
+						Arguments: testArgs(map[string]any{
 							"name":   "John",
 							"age":    int64(30),
 							"active": true,
-						},
+						}),
 					},
 				},
 			},
@@ -257,7 +257,7 @@ get_weather(location="New York")</function_calls>`,
 			if diff := cmp.Diff(thinking, tt.expectedThinking); diff != "" {
 				t.Errorf("thinking mismatch (-got +want):\n%s", diff)
 			}
-			if diff := cmp.Diff(calls, tt.expectedCalls); diff != "" {
+			if diff := cmp.Diff(calls, tt.expectedCalls, argsComparer); diff != "" {
 				t.Errorf("calls mismatch (-got +want):\n%s", diff)
 			}
 		})
@@ -283,7 +283,7 @@ func TestOlmo3Parser_Streaming(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: map[string]any{"location": "SF"},
+						Arguments: testArgs(map[string]any{"location": "SF"}),
 					},
 				},
 			},
@@ -296,7 +296,7 @@ func TestOlmo3Parser_Streaming(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: map[string]any{"location": "NYC"},
+						Arguments: testArgs(map[string]any{"location": "NYC"}),
 					},
 				},
 			},
@@ -308,7 +308,7 @@ func TestOlmo3Parser_Streaming(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "test",
-						Arguments: map[string]any{},
+						Arguments: testArgs(map[string]any{}),
 					},
 				},
 			},
@@ -343,7 +343,7 @@ func TestOlmo3Parser_Streaming(t *testing.T) {
 			if diff := cmp.Diff(allContent, tt.expectedContent); diff != "" {
 				t.Errorf("content mismatch (-got +want):\n%s", diff)
 			}
-			if diff := cmp.Diff(allCalls, tt.expectedCalls); diff != "" {
+			if diff := cmp.Diff(allCalls, tt.expectedCalls, argsComparer); diff != "" {
 				t.Errorf("calls mismatch (-got +want):\n%s", diff)
 			}
 		})
@@ -378,7 +378,7 @@ func TestParseOlmo3FunctionCalls(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: map[string]any{"location": "SF"},
+						Arguments: testArgs(map[string]any{"location": "SF"}),
 					},
 				},
 			},
@@ -390,11 +390,11 @@ func TestParseOlmo3FunctionCalls(t *testing.T) {
 				{
 					Function: api.ToolCallFunction{
 						Name: "send_email",
-						Arguments: map[string]any{
+						Arguments: testArgs(map[string]any{
 							"to":      "user@example.com",
 							"subject": "Hello",
 							"body":    "Test message",
-						},
+						}),
 					},
 				},
 			},
@@ -407,13 +407,13 @@ get_time(timezone="PST")`,
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: map[string]any{"location": "SF"},
+						Arguments: testArgs(map[string]any{"location": "SF"}),
 					},
 				},
 				{
 					Function: api.ToolCallFunction{
 						Name:      "get_time",
-						Arguments: map[string]any{"timezone": "PST"},
+						Arguments: testArgs(map[string]any{"timezone": "PST"}),
 					},
 				},
 			},
@@ -437,7 +437,7 @@ get_time(timezone="PST")`,
 				t.Errorf("parseOlmo3FunctionCalls() error = %v, wantErr %v", err, tt.wantErr)
 				return
 			}
-			if diff := cmp.Diff(calls, tt.expected); diff != "" {
+			if diff := cmp.Diff(calls, tt.expected, argsComparer); diff != "" {
 				t.Errorf("calls mismatch (-got +want):\n%s", diff)
 			}
 		})

model/parsers/qwen3coder.go

@@ -270,12 +270,12 @@ func parseToolCall(raw qwenEventRawToolCall, tools []api.Tool) (api.ToolCall, er
 		}
 	}
 
-	toolCall.Function.Arguments = make(api.ToolCallFunctionArguments)
+	toolCall.Function.Arguments = api.NewToolCallFunctionArguments()
 	for _, parameter := range functionCall.Parameters {
 		// Look up the parameter type if we found the tool
 		var paramType api.PropertyType
 		if matchedTool != nil && matchedTool.Function.Parameters.Properties != nil {
-			if prop, ok := matchedTool.Function.Parameters.Properties[parameter.Name]; ok {
+			if prop, ok := matchedTool.Function.Parameters.Properties.Get(parameter.Name); ok {
 				// Handle anyOf by collecting all types from the union
 				if len(prop.AnyOf) > 0 {
 					for _, anyOfProp := range prop.AnyOf {
@@ -287,7 +287,7 @@ func parseToolCall(raw qwenEventRawToolCall, tools []api.Tool) (api.ToolCall, er
 			}
 		}
 
-		toolCall.Function.Arguments[parameter.Name] = parseValue(parameter.Value, paramType)
+		toolCall.Function.Arguments.Set(parameter.Name, parseValue(parameter.Value, paramType))
 	}
 
 	return toolCall, nil

model/parsers/qwen3coder_test.go

@@ -11,7 +11,7 @@ import (
 func tool(name string, props map[string]api.ToolProperty) api.Tool {
 	t := api.Tool{Type: "function", Function: api.ToolFunction{Name: name}}
 	t.Function.Parameters.Type = "object"
-	t.Function.Parameters.Properties = props
+	t.Function.Parameters.Properties = testPropsMap(props)
 	return t
 }
 
@@ -369,10 +369,10 @@ celsius
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "get_current_temperature",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"location": "San Francisco",
 						"unit":     "celsius",
-					},
+					}),
 				},
 			},
 		},
@@ -390,10 +390,10 @@ celsius
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "get current temperature",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"location with spaces": "San Francisco",
 						"unit with spaces":     "celsius",
-					},
+					}),
 				},
 			},
 		},
@@ -415,10 +415,10 @@ San Francisco
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "\"get current temperature\"",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"\"location with spaces\"": "San Francisco",
 						"\"unit with spaces\"":     "\"celsius\"",
-					},
+					}),
 				},
 			},
 		},
@@ -449,12 +449,12 @@ true
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "calculate",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"x":       3.14,
 						"y":       42,
 						"enabled": true,
 						"items":   []any{"a", "b", "c"},
-					},
+					}),
 				},
 			},
 		},
@@ -470,9 +470,9 @@ ls && echo "done"
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "exec",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"command": "ls && echo \"done\"",
-					},
+					}),
 				},
 			},
 		},
@@ -487,9 +487,9 @@ ls && echo "a > b and a < b"
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "exec",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"command": "ls && echo \"a > b and a < b\"",
-					},
+					}),
 				},
 			},
 		},
@@ -507,10 +507,10 @@ Hello! 你好! 🌟 مرحبا
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "获取天气",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"城市":      "北京",
 						"message": "Hello! 你好! 🌟 مرحبا",
-					},
+					}),
 				},
 			},
 		},
@@ -521,7 +521,7 @@ Hello! 你好! 🌟 مرحبا
 		if err != nil {
 			t.Errorf("step %d (%s): %v", i, step.name, err)
 		}
-		if !reflect.DeepEqual(gotToolCall, step.wantToolCall) {
+		if !toolCallEqual(gotToolCall, step.wantToolCall) {
 			t.Errorf("step %d (%s): got tool call %#v, want %#v", i, step.name, gotToolCall, step.wantToolCall)
 		}
 	}

model/parsers/qwen3vl_nonthinking_test.go

@@ -550,10 +550,10 @@ func TestQwen3VLNonThinkingToolParser(t *testing.T) {
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "get-current-weather",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"location": "San Francisco, CA",
 						"unit":     "fahrenheit",
-					},
+					}),
 				},
 			},
 		},
@@ -564,10 +564,10 @@ func TestQwen3VLNonThinkingToolParser(t *testing.T) {
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "get current temperature",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"location with spaces": "San Francisco",
 						"unit with spaces":     "celsius",
-					},
+					}),
 				},
 			},
 		},
@@ -578,10 +578,10 @@ func TestQwen3VLNonThinkingToolParser(t *testing.T) {
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "\"get current temperature\"",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"\"location with spaces\"": "San Francisco",
 						"\"unit with spaces\"":     "\"celsius\"",
-					},
+					}),
 				},
 			},
 		},
@@ -592,12 +592,12 @@ func TestQwen3VLNonThinkingToolParser(t *testing.T) {
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "calculate",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"x":       3.14,
 						"y":       float64(42),
 						"enabled": true,
 						"items":   []any{"a", "b", "c"},
-					},
+					}),
 				},
 			},
 		},
@@ -608,9 +608,9 @@ func TestQwen3VLNonThinkingToolParser(t *testing.T) {
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "exec",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"command": "ls && echo \"done\"",
-					},
+					}),
 				},
 			},
 		},
@@ -621,9 +621,9 @@ func TestQwen3VLNonThinkingToolParser(t *testing.T) {
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "exec",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"command": "ls && echo \"a > b and a < b\"",
-					},
+					}),
 				},
 			},
 		},
@@ -634,10 +634,10 @@ func TestQwen3VLNonThinkingToolParser(t *testing.T) {
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "获取天气",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"城市":      "北京",
 						"message": "Hello! 你好! 🌟 مرحبا",
-					},
+					}),
 				},
 			},
 		},
@@ -648,7 +648,7 @@ func TestQwen3VLNonThinkingToolParser(t *testing.T) {
 		if err != nil {
 			t.Errorf("step %d (%s): %v", i, step.name, err)
 		}
-		if !reflect.DeepEqual(gotToolCall, step.wantToolCall) {
+		if !toolCallEqual(gotToolCall, step.wantToolCall) {
 			t.Errorf("step %d (%s): got tool call %#v, want %#v", i, step.name, gotToolCall, step.wantToolCall)
 		}
 	}

model/parsers/qwen3vl_thinking_test.go

@@ -241,10 +241,10 @@ func TestQwen3VLThinkingToolParser(t *testing.T) {
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "get-current-weather",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"location": "San Francisco, CA",
 						"unit":     "fahrenheit",
-					},
+					}),
 				},
 			},
 		},
@@ -255,10 +255,10 @@ func TestQwen3VLThinkingToolParser(t *testing.T) {
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "get current temperature",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"location with spaces": "San Francisco",
 						"unit with spaces":     "celsius",
-					},
+					}),
 				},
 			},
 		},
@@ -269,10 +269,10 @@ func TestQwen3VLThinkingToolParser(t *testing.T) {
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "\"get current temperature\"",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"\"location with spaces\"": "San Francisco",
 						"\"unit with spaces\"":     "\"celsius\"",
-					},
+					}),
 				},
 			},
 		},
@@ -283,12 +283,12 @@ func TestQwen3VLThinkingToolParser(t *testing.T) {
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "calculate",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"x":       3.14,
 						"y":       float64(42),
 						"enabled": true,
 						"items":   []any{"a", "b", "c"},
-					},
+					}),
 				},
 			},
 		},
@@ -299,9 +299,9 @@ func TestQwen3VLThinkingToolParser(t *testing.T) {
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "exec",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"command": "ls && echo \"done\"",
-					},
+					}),
 				},
 			},
 		},
@@ -312,9 +312,9 @@ func TestQwen3VLThinkingToolParser(t *testing.T) {
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "exec",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"command": "ls && echo \"a > b and a < b\"",
-					},
+					}),
 				},
 			},
 		},
@@ -325,10 +325,10 @@ func TestQwen3VLThinkingToolParser(t *testing.T) {
 			wantToolCall: api.ToolCall{
 				Function: api.ToolCallFunction{
 					Name: "获取天气",
-					Arguments: map[string]any{
+					Arguments: testArgs(map[string]any{
 						"城市":      "北京",
 						"message": "Hello! 你好! 🌟 مرحبا",
-					},
+					}),
 				},
 			},
 		},
@@ -339,7 +339,7 @@ func TestQwen3VLThinkingToolParser(t *testing.T) {
 		if err != nil {
 			t.Errorf("step %d (%s): %v", i, step.name, err)
 		}
-		if !reflect.DeepEqual(gotToolCall, step.wantToolCall) {
+		if !toolCallEqual(gotToolCall, step.wantToolCall) {
 			t.Errorf("step %d (%s): got tool call %#v, want %#v", i, step.name, gotToolCall, step.wantToolCall)
 		}
 	}

model/parsers/testhelpers_test.go

@@ -0,0 +1,98 @@
+package parsers
+
+import (
+	"encoding/json"
+
+	"github.com/google/go-cmp/cmp"
+	"github.com/ollama/ollama/api"
+)
+
+// argsComparer provides cmp options for comparing ToolCallFunctionArguments
+// It compares by logical equality (same keys with same values) not by order
+var argsComparer = cmp.Comparer(func(a, b api.ToolCallFunctionArguments) bool {
+	// Convert both to maps and compare
+	aMap := a.ToMap()
+	bMap := b.ToMap()
+	if len(aMap) != len(bMap) {
+		return false
+	}
+	for k, av := range aMap {
+		bv, ok := bMap[k]
+		if !ok {
+			return false
+		}
+		// Use JSON encoding for deep comparison of values
+		aJSON, _ := json.Marshal(av)
+		bJSON, _ := json.Marshal(bv)
+		if string(aJSON) != string(bJSON) {
+			return false
+		}
+	}
+	return true
+})
+
+// propsComparer provides cmp options for comparing ToolPropertiesMap
+var propsComparer = cmp.Comparer(func(a, b *api.ToolPropertiesMap) bool {
+	if a == nil && b == nil {
+		return true
+	}
+	if a == nil || b == nil {
+		return false
+	}
+	aJSON, _ := json.Marshal(a)
+	bJSON, _ := json.Marshal(b)
+	return string(aJSON) == string(bJSON)
+})
+
+// toolsComparer combines argsComparer and propsComparer for comparing tools
+var toolsComparer = cmp.Options{argsComparer, propsComparer}
+
+// toolCallEqual compares two tool calls by comparing their components
+// It compares arguments by logical equality (same keys with same values) not by order
+func toolCallEqual(a, b api.ToolCall) bool {
+	if a.ID != b.ID {
+		return false
+	}
+	if a.Function.Index != b.Function.Index {
+		return false
+	}
+	if a.Function.Name != b.Function.Name {
+		return false
+	}
+	// Compare arguments by logical equality using argsComparer logic
+	aMap := a.Function.Arguments.ToMap()
+	bMap := b.Function.Arguments.ToMap()
+	if len(aMap) != len(bMap) {
+		return false
+	}
+	for k, av := range aMap {
+		bv, ok := bMap[k]
+		if !ok {
+			return false
+		}
+		aJSON, _ := json.Marshal(av)
+		bJSON, _ := json.Marshal(bv)
+		if string(aJSON) != string(bJSON) {
+			return false
+		}
+	}
+	return true
+}
+
+// testPropsMap creates a ToolPropertiesMap from a map (convenience function for tests, order not preserved)
+func testPropsMap(m map[string]api.ToolProperty) *api.ToolPropertiesMap {
+	props := api.NewToolPropertiesMap()
+	for k, v := range m {
+		props.Set(k, v)
+	}
+	return props
+}
+
+// testArgs creates ToolCallFunctionArguments from a map (convenience function for tests, order not preserved)
+func testArgs(m map[string]any) api.ToolCallFunctionArguments {
+	args := api.NewToolCallFunctionArguments()
+	for k, v := range m {
+		args.Set(k, v)
+	}
+	return args
+}

model/renderers/cogito_test.go

@@ -94,12 +94,12 @@ You are a helpful assistant.
 						Description: "Get current weather",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"location": {
 									Type:        api.PropertyType{"string"},
 									Description: "City name",
 								},
-							},
+							}),
 							Required: []string{"location"},
 						},
 					},
@@ -139,9 +139,9 @@ You have the following functions available:
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "Paris",
-								},
+								}),
 							},
 						},
 					},
@@ -162,9 +162,9 @@ You have the following functions available:
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "Paris",
-								},
+								}),
 							},
 						},
 					},
@@ -186,17 +186,17 @@ You have the following functions available:
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "Paris",
-								},
+								}),
 							},
 						},
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "London",
-								},
+								}),
 							},
 						},
 					},
@@ -226,12 +226,12 @@ You have the following functions available:
 						Description: "Get current weather",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"location": {
 									Type:        api.PropertyType{"string"},
 									Description: "City name",
 								},
-							},
+							}),
 							Required: []string{"location"},
 						},
 					},
@@ -378,9 +378,9 @@ You are a pirate chatbot who always responds in pirate speak!
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "Paris",
-								},
+								}),
 							},
 						},
 					},
@@ -401,14 +401,14 @@ You are a pirate chatbot who always responds in pirate speak!
 						{
 							Function: api.ToolCallFunction{
 								Name: "process_data",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgsOrdered([]orderedArg{
-									"items": []any{"item1", "item2", "item3"},
+									{"config", map[string]any{
-									"config": map[string]any{
 										"enabled":   true,
 										"threshold": 0.95,
 										"tags":      []string{"important", "urgent"},
-									},
+									}},
-								},
+									{"items", []any{"item1", "item2", "item3"}},
+								}),
 							},
 						},
 					},

model/renderers/deepseek3_test.go

@@ -82,9 +82,9 @@ Second instruction<｜User｜>Hello<｜Assistant｜></think>`,
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "Paris",
-								},
+								}),
 							},
 						},
 					},
@@ -104,9 +104,9 @@ Second instruction<｜User｜>Hello<｜Assistant｜></think>`,
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "Paris",
-								},
+								}),
 							},
 						},
 					},
@@ -125,9 +125,9 @@ Second instruction<｜User｜>Hello<｜Assistant｜></think>`,
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "Paris",
-								},
+								}),
 							},
 						},
 					},
@@ -147,17 +147,17 @@ Second instruction<｜User｜>Hello<｜Assistant｜></think>`,
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "Paris",
-								},
+								}),
 							},
 						},
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "London",
-								},
+								}),
 							},
 						},
 					},
@@ -214,9 +214,9 @@ Second instruction<｜User｜>Hello<｜Assistant｜></think>`,
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "Paris",
-								},
+								}),
 							},
 						},
 					},
@@ -235,9 +235,9 @@ Second instruction<｜User｜>Hello<｜Assistant｜></think>`,
 						{
 							Function: api.ToolCallFunction{
 								Name: "process",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"data": "test",
-								},
+								}),
 							},
 						},
 					},
@@ -281,9 +281,9 @@ Second instruction<｜User｜>Hello<｜Assistant｜></think>`,
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "Paris",
-								},
+								}),
 							},
 						},
 					},
@@ -305,9 +305,9 @@ Second instruction<｜User｜>Hello<｜Assistant｜></think>`,
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "Paris",
-								},
+								}),
 							},
 						},
 					},
@@ -355,9 +355,9 @@ Second instruction<｜User｜>Hello<｜Assistant｜></think>`,
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "Paris",
-								},
+								}),
 							},
 						},
 					},
@@ -379,9 +379,9 @@ Second instruction<｜User｜>Hello<｜Assistant｜></think>`,
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "Paris",
-								},
+								}),
 							},
 						},
 					},
@@ -436,17 +436,17 @@ Second instruction<｜User｜>Hello<｜Assistant｜></think>`,
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "Tokyo",
-								},
+								}),
 							},
 						},
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "New York",
-								},
+								}),
 							},
 						},
 					},
@@ -489,12 +489,12 @@ Second instruction<｜User｜>Hello<｜Assistant｜></think>`,
 						Description: "Get current weather information",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"location": {
 									Type:        api.PropertyType{"string"},
 									Description: "City name",
 								},
-							},
+							}),
 							Required: []string{"location"},
 						},
 					},
@@ -535,12 +535,12 @@ Where:
 						Description: "Get current weather information",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"location": {
 									Type:        api.PropertyType{"string"},
 									Description: "City name",
 								},
-							},
+							}),
 							Required: []string{"location"},
 						},
 					},
@@ -578,9 +578,9 @@ Where:
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "Paris",
-								},
+								}),
 							},
 						},
 					},
@@ -594,12 +594,12 @@ Where:
 						Description: "Get current weather information",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"location": {
 									Type:        api.PropertyType{"string"},
 									Description: "City name",
 								},
-							},
+							}),
 							Required: []string{"location"},
 						},
 					},
@@ -638,9 +638,9 @@ Where:
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "Paris",
-								},
+								}),
 							},
 						},
 					},
@@ -656,12 +656,12 @@ Where:
 						Description: "Get current weather information",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"location": {
 									Type:        api.PropertyType{"string"},
 									Description: "City name",
 								},
-							},
+							}),
 							Required: []string{"location"},
 						},
 					},
@@ -701,9 +701,9 @@ Where:
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "Tokyo",
-								},
+								}),
 							},
 						},
 					},
@@ -724,12 +724,12 @@ Where:
 						Description: "Get current weather information",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"location": {
 									Type:        api.PropertyType{"string"},
 									Description: "City name",
 								},
-							},
+							}),
 							Required: []string{"location"},
 						},
 					},
@@ -770,12 +770,12 @@ Where:
 						Description: "Get current weather information",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"location": {
 									Type:        api.PropertyType{"string"},
 									Description: "City name",
 								},
-							},
+							}),
 							Required: []string{"location"},
 						},
 					},
@@ -787,12 +787,12 @@ Where:
 						Description: "Perform mathematical calculations",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"expression": {
 									Type:        api.PropertyType{"string"},
 									Description: "Mathematical expression to evaluate",
 								},
-							},
+							}),
 							Required: []string{"expression"},
 						},
 					},
@@ -834,17 +834,17 @@ Where:
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "Paris",
-								},
+								}),
 							},
 						},
 						{
 							Function: api.ToolCallFunction{
 								Name: "calculate",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"expression": "25 * 4",
-								},
+								}),
 							},
 						},
 					},
@@ -860,12 +860,12 @@ Where:
 						Description: "Get current weather information",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"location": {
 									Type:        api.PropertyType{"string"},
 									Description: "City name",
 								},
-							},
+							}),
 							Required: []string{"location"},
 						},
 					},
@@ -877,12 +877,12 @@ Where:
 						Description: "Perform mathematical calculations",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"expression": {
 									Type:        api.PropertyType{"string"},
 									Description: "Mathematical expression to evaluate",
 								},
-							},
+							}),
 							Required: []string{"expression"},
 						},
 					},
@@ -927,12 +927,12 @@ Where:
 						Description: "Get current weather information",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"location": {
 									Type:        api.PropertyType{"string"},
 									Description: "City name",
 								},
-							},
+							}),
 							Required: []string{"location"},
 						},
 					},

model/renderers/functiongemma.go

@@ -136,7 +136,7 @@ func (r *FunctionGemmaRenderer) renderToolDeclaration(tool api.Tool) string {
 		needsComma := false
 
 		// Only include properties:{} if there are actual properties
-		if len(fn.Parameters.Properties) > 0 {
+		if fn.Parameters.Properties != nil && fn.Parameters.Properties.Len() > 0 {
 			sb.WriteString("properties:{")
 			r.writeProperties(&sb, fn.Parameters.Properties)
 			sb.WriteString("}")
@@ -172,16 +172,16 @@ func (r *FunctionGemmaRenderer) renderToolDeclaration(tool api.Tool) string {
 	return sb.String()
 }
 
-func (r *FunctionGemmaRenderer) writeProperties(sb *strings.Builder, props map[string]api.ToolProperty) {
+func (r *FunctionGemmaRenderer) writeProperties(sb *strings.Builder, props *api.ToolPropertiesMap) {
-	keys := make([]string, 0, len(props))
+	keys := make([]string, 0, props.Len())
-	for k := range props {
+	for k := range props.All() {
 		keys = append(keys, k)
 	}
 	sort.Strings(keys)
 
 	first := true
 	for _, name := range keys {
-		prop := props[name]
+		prop, _ := props.Get(name)
 		if !first {
 			sb.WriteString(",")
 		}
@@ -203,15 +203,15 @@ func (r *FunctionGemmaRenderer) formatToolCall(tc api.ToolCall) string {
 	var sb strings.Builder
 	sb.WriteString("<start_function_call>call:" + tc.Function.Name + "{")
 
-	keys := make([]string, 0, len(tc.Function.Arguments))
+	keys := make([]string, 0, tc.Function.Arguments.Len())
-	for k := range tc.Function.Arguments {
+	for k := range tc.Function.Arguments.All() {
 		keys = append(keys, k)
 	}
 	sort.Strings(keys)
 
 	first := true
 	for _, key := range keys {
-		value := tc.Function.Arguments[key]
+		value, _ := tc.Function.Arguments.Get(key)
 		if !first {
 			sb.WriteString(",")
 		}

model/renderers/functiongemma_test.go

@@ -51,9 +51,9 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						Description: "Get weather",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"city": {Type: api.PropertyType{"string"}, Description: "City"},
-							},
+							}),
 						},
 					},
 				},
@@ -75,9 +75,9 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						Description: "Get weather",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"city": {Type: api.PropertyType{"string"}, Description: "City"},
-							},
+							}),
 						},
 					},
 				},
@@ -107,9 +107,9 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						Description: "Get weather",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"city": {Type: api.PropertyType{"string"}, Description: "City"},
-							},
+							}),
 						},
 					},
 				},
@@ -126,7 +126,7 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						{
 							Function: api.ToolCallFunction{
 								Name:      "get_weather",
-								Arguments: api.ToolCallFunctionArguments{"city": "Paris"},
+								Arguments: testArgs(map[string]any{"city": "Paris"}),
 							},
 						},
 					},
@@ -141,9 +141,9 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						Description: "Get weather",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"city": {Type: api.PropertyType{"string"}, Description: "City"},
-							},
+							}),
 						},
 					},
 				},
@@ -161,7 +161,7 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						{
 							Function: api.ToolCallFunction{
 								Name:      "get_weather",
-								Arguments: api.ToolCallFunctionArguments{"city": "Paris"},
+								Arguments: testArgs(map[string]any{"city": "Paris"}),
 							},
 						},
 					},
@@ -176,9 +176,9 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						Description: "Get weather",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"city": {Type: api.PropertyType{"string"}, Description: "City"},
-							},
+							}),
 						},
 					},
 				},
@@ -195,7 +195,7 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						{
 							Function: api.ToolCallFunction{
 								Name:      "add",
-								Arguments: api.ToolCallFunctionArguments{"a": float64(1), "b": float64(2)},
+								Arguments: testArgs(map[string]any{"a": float64(1), "b": float64(2)}),
 							},
 						},
 					},
@@ -210,10 +210,10 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						Description: "Add numbers",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"a": {Type: api.PropertyType{"number"}},
 								"b": {Type: api.PropertyType{"number"}},
-							},
+							}),
 						},
 					},
 				},
@@ -239,10 +239,10 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						Parameters: api.ToolFunctionParameters{
 							Type:     "object",
 							Required: []string{"city"},
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"city":    {Type: api.PropertyType{"string"}, Description: "City Name"},
 								"country": {Type: api.PropertyType{"string"}, Description: "Country Name"},
-							},
+							}),
 						},
 					},
 				},
@@ -263,9 +263,9 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						Description: "Get weather",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"city": {Type: api.PropertyType{"string"}, Description: "City"},
-							},
+							}),
 						},
 					},
 				},
@@ -276,9 +276,9 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						Description: "Get current time",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"timezone": {Type: api.PropertyType{"string"}, Description: "Timezone"},
-							},
+							}),
 						},
 					},
 				},
@@ -296,13 +296,13 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						{
 							Function: api.ToolCallFunction{
 								Name:      "get_weather",
-								Arguments: api.ToolCallFunctionArguments{"city": "Paris"},
+								Arguments: testArgs(map[string]any{"city": "Paris"}),
 							},
 						},
 						{
 							Function: api.ToolCallFunction{
 								Name:      "get_time",
-								Arguments: api.ToolCallFunctionArguments{"timezone": "UTC"},
+								Arguments: testArgs(map[string]any{"timezone": "UTC"}),
 							},
 						},
 					},
@@ -318,9 +318,9 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						Description: "Get weather",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"city": {Type: api.PropertyType{"string"}, Description: "City"},
-							},
+							}),
 						},
 					},
 				},
@@ -331,9 +331,9 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						Description: "Get current time",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"timezone": {Type: api.PropertyType{"string"}, Description: "Timezone"},
-							},
+							}),
 						},
 					},
 				},
@@ -351,7 +351,7 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						{
 							Function: api.ToolCallFunction{
 								Name:      "get_weather",
-								Arguments: api.ToolCallFunctionArguments{"city": "Paris"},
+								Arguments: testArgs(map[string]any{"city": "Paris"}),
 							},
 						},
 					},
@@ -367,9 +367,9 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						Description: "Get weather",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"city": {Type: api.PropertyType{"string"}, Description: "City"},
-							},
+							}),
 						},
 					},
 				},
@@ -391,7 +391,7 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						Description: "",
 						Parameters: api.ToolFunctionParameters{
 							Type:       "object",
-							Properties: map[string]api.ToolProperty{},
+							Properties: testPropsMap(map[string]api.ToolProperty{}),
 						},
 					},
 				},
@@ -430,7 +430,7 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						{
 							Function: api.ToolCallFunction{
 								Name:      "set_flag",
-								Arguments: api.ToolCallFunctionArguments{"enabled": true},
+								Arguments: testArgs(map[string]any{"enabled": true}),
 							},
 						},
 					},
@@ -445,9 +445,9 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						Description: "Set a flag",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"enabled": {Type: api.PropertyType{"boolean"}, Description: "Flag value"},
-							},
+							}),
 						},
 					},
 				},
@@ -468,11 +468,11 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						Parameters: api.ToolFunctionParameters{
 							Type:     "object",
 							Required: []string{"a", "b", "c"},
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"a": {Type: api.PropertyType{"string"}, Description: "A"},
 								"b": {Type: api.PropertyType{"string"}, Description: "B"},
 								"c": {Type: api.PropertyType{"string"}, Description: "C"},
-							},
+							}),
 						},
 					},
 				},
@@ -492,9 +492,9 @@ func TestFunctionGemmaRenderer(t *testing.T) {
 						Description: "Test",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"items": {Type: api.PropertyType{"array"}, Description: "List of items"},
-							},
+							}),
 						},
 					},
 				},

model/renderers/nemotron3nano.go

@@ -114,7 +114,7 @@ func (r *Nemotron3NanoRenderer) renderTools(tools []api.Tool) string {
 
 		sb.WriteString("\n<parameters>")
 		if fn.Parameters.Properties != nil {
-			for paramName, paramFields := range fn.Parameters.Properties {
+			for paramName, paramFields := range fn.Parameters.Properties.All() {
 				sb.WriteString("\n<parameter>")
 				sb.WriteString("\n<name>" + paramName + "</name>")
 
@@ -202,7 +202,7 @@ func (r *Nemotron3NanoRenderer) formatContent(content string, truncate bool, add
 func (r *Nemotron3NanoRenderer) writeToolCalls(sb *strings.Builder, toolCalls []api.ToolCall) {
 	for _, tc := range toolCalls {
 		sb.WriteString("<tool_call>\n<function=" + tc.Function.Name + ">\n")
-		for name, value := range tc.Function.Arguments {
+		for name, value := range tc.Function.Arguments.All() {
 			sb.WriteString("<parameter=" + name + ">\n" + r.formatArgValue(value) + "\n</parameter>\n")
 		}
 		sb.WriteString("</function>\n</tool_call>\n")

model/renderers/nemotron3nano_test.go

@@ -75,9 +75,9 @@ func TestNemotron3NanoRenderer(t *testing.T) {
 						Parameters: api.ToolFunctionParameters{
 							Type:     "object",
 							Required: []string{"city"},
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"city": {Type: api.PropertyType{"string"}, Description: "The city name"},
-							},
+							}),
 						},
 					},
 				},
@@ -113,7 +113,7 @@ func TestNemotron3NanoRenderer(t *testing.T) {
 						{
 							Function: api.ToolCallFunction{
 								Name:      "get_weather",
-								Arguments: map[string]any{"city": "Paris"},
+								Arguments: testArgs(map[string]any{"city": "Paris"}),
 							},
 						},
 					},
@@ -129,9 +129,9 @@ func TestNemotron3NanoRenderer(t *testing.T) {
 						Parameters: api.ToolFunctionParameters{
 							Type:     "object",
 							Required: []string{"city"},
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"city": {Type: api.PropertyType{"string"}, Description: "The city name"},
-							},
+							}),
 						},
 					},
 				},
@@ -171,7 +171,7 @@ func TestNemotron3NanoRenderer(t *testing.T) {
 						{
 							Function: api.ToolCallFunction{
 								Name:      "get_weather",
-								Arguments: map[string]any{"city": "Paris"},
+								Arguments: testArgs(map[string]any{"city": "Paris"}),
 							},
 						},
 					},
@@ -185,9 +185,9 @@ func TestNemotron3NanoRenderer(t *testing.T) {
 						Name: "get_weather",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"city": {Type: api.PropertyType{"string"}},
-							},
+							}),
 						},
 					},
 				},
@@ -238,13 +238,13 @@ func TestNemotron3NanoRenderer(t *testing.T) {
 						{
 							Function: api.ToolCallFunction{
 								Name:      "get_weather",
-								Arguments: map[string]any{"city": "Paris"},
+								Arguments: testArgs(map[string]any{"city": "Paris"}),
 							},
 						},
 						{
 							Function: api.ToolCallFunction{
 								Name:      "get_weather",
-								Arguments: map[string]any{"city": "London"},
+								Arguments: testArgs(map[string]any{"city": "London"}),
 							},
 						},
 					},
@@ -259,9 +259,9 @@ func TestNemotron3NanoRenderer(t *testing.T) {
 						Name: "get_weather",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"city": {Type: api.PropertyType{"string"}},
-							},
+							}),
 						},
 					},
 				},
@@ -304,13 +304,13 @@ func TestNemotron3NanoRenderer(t *testing.T) {
 			msgs: []api.Message{
 				{Role: "user", Content: "What's the weather in Paris and London? Also, what's 2+2?"},
 				{Role: "assistant", Content: "", Thinking: "I need to check the weather for both cities and calculate 2+2. Let me start with the weather calls.", ToolCalls: []api.ToolCall{
-					{Function: api.ToolCallFunction{Name: "get_weather", Arguments: api.ToolCallFunctionArguments{"city": "Paris"}}},
+					{Function: api.ToolCallFunction{Name: "get_weather", Arguments: testArgs(map[string]any{"city": "Paris"})}},
-					{Function: api.ToolCallFunction{Name: "get_weather", Arguments: api.ToolCallFunctionArguments{"city": "London"}}},
+					{Function: api.ToolCallFunction{Name: "get_weather", Arguments: testArgs(map[string]any{"city": "London"})}},
 				}},
 				{Role: "tool", Content: "Sunny, 22°C", ToolCallID: "call1"},
 				{Role: "tool", Content: "Rainy, 15°C", ToolCallID: "call2"},
 				{Role: "assistant", Content: "", Thinking: "Now I have the weather data. Let me calculate 2+2.", ToolCalls: []api.ToolCall{
-					{Function: api.ToolCallFunction{Name: "calculate", Arguments: api.ToolCallFunctionArguments{"expression": "2+2"}}},
+					{Function: api.ToolCallFunction{Name: "calculate", Arguments: testArgs(map[string]any{"expression": "2+2"})}},
 				}},
 				{Role: "tool", Content: "4", ToolCallID: "call3"},
 				{Role: "assistant", Content: "Based on the weather data, Paris is sunny at 22°C and London is rainy at 15°C. Also, 2+2 equals 4.", Thinking: "Perfect! I have all the information needed to provide a complete answer."},
@@ -322,9 +322,9 @@ func TestNemotron3NanoRenderer(t *testing.T) {
 						Name: "get_weather",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"city": {Type: api.PropertyType{"string"}},
-							},
+							}),
 						},
 					},
 				},
@@ -334,9 +334,9 @@ func TestNemotron3NanoRenderer(t *testing.T) {
 						Name: "calculate",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"expression": {Type: api.PropertyType{"string"}},
-							},
+							}),
 						},
 					},
 				},
@@ -389,7 +389,7 @@ func TestNemotron3NanoRenderer(t *testing.T) {
 				{
 					Role: "assistant",
 					ToolCalls: []api.ToolCall{
-						{Function: api.ToolCallFunction{Name: "get_user", Arguments: map[string]any{"id": "123"}}},
+						{Function: api.ToolCallFunction{Name: "get_user", Arguments: testArgs(map[string]any{"id": "123"})}},
 					},
 				},
 				{Role: "tool", Content: `{"name": "John", "age": 30, "active": true}`},
@@ -401,7 +401,7 @@ func TestNemotron3NanoRenderer(t *testing.T) {
 						Name: "get_user",
 						Parameters: api.ToolFunctionParameters{
 							Type:       "object",
-							Properties: map[string]api.ToolProperty{"id": {Type: api.PropertyType{"string"}}},
+							Properties: testPropsMap(map[string]api.ToolProperty{"id": {Type: api.PropertyType{"string"}}}),
 						},
 					},
 				},
@@ -450,9 +450,9 @@ func TestNemotron3NanoRenderer(t *testing.T) {
 					ToolCalls: []api.ToolCall{
 						{Function: api.ToolCallFunction{
 							Name: "create",
-							Arguments: map[string]any{
+							Arguments: testArgs(map[string]any{
 								"data": map[string]any{"nested": "value", "count": 42},
-							},
+							}),
 						}},
 					},
 				},
@@ -465,7 +465,7 @@ func TestNemotron3NanoRenderer(t *testing.T) {
 						Name: "create",
 						Parameters: api.ToolFunctionParameters{
 							Type:       "object",
-							Properties: map[string]api.ToolProperty{"data": {Type: api.PropertyType{"object"}}},
+							Properties: testPropsMap(map[string]api.ToolProperty{"data": {Type: api.PropertyType{"object"}}}),
 						},
 					},
 				},
@@ -512,7 +512,7 @@ func TestNemotron3NanoRenderer(t *testing.T) {
 				{
 					Role: "assistant",
 					ToolCalls: []api.ToolCall{
-						{Function: api.ToolCallFunction{Name: "translate", Arguments: map[string]any{"text": "你好"}}},
+						{Function: api.ToolCallFunction{Name: "translate", Arguments: testArgs(map[string]any{"text": "你好"})}},
 					},
 				},
 				{Role: "tool", Content: "Hello"},
@@ -524,9 +524,9 @@ func TestNemotron3NanoRenderer(t *testing.T) {
 						Name: "translate",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"text": {Type: api.PropertyType{"string"}},
-							},
+							}),
 						},
 					},
 				},

model/renderers/olmo3.go

@@ -100,8 +100,8 @@ func (r *Olmo3Renderer) Render(messages []api.Message, tools []api.Tool, _ *api.
 					sb.WriteString("(")
 
 					// Get sorted keys for deterministic output
-					keys := make([]string, 0, len(tc.Function.Arguments))
+					keys := make([]string, 0, tc.Function.Arguments.Len())
-					for k := range tc.Function.Arguments {
+					for k := range tc.Function.Arguments.All() {
 						keys = append(keys, k)
 					}
 					sort.Strings(keys)
@@ -110,7 +110,8 @@ func (r *Olmo3Renderer) Render(messages []api.Message, tools []api.Tool, _ *api.
 						if k > 0 {
 							sb.WriteString(", ")
 						}
-						value, err := json.Marshal(tc.Function.Arguments[key])
+						val, _ := tc.Function.Arguments.Get(key)
+						value, err := json.Marshal(val)
 						if err != nil {
 							return "", err
 						}

model/renderers/olmo3_test.go

@@ -53,9 +53,9 @@ func TestOlmo3Renderer(t *testing.T) {
 						Parameters: api.ToolFunctionParameters{
 							Type:     "object",
 							Required: []string{"location"},
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"location": {Type: api.PropertyType{"string"}, Description: "The city"},
-							},
+							}),
 						},
 					},
 				},
@@ -80,9 +80,9 @@ func TestOlmo3Renderer(t *testing.T) {
 						Parameters: api.ToolFunctionParameters{
 							Type:     "object",
 							Required: []string{"location"},
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"location": {Type: api.PropertyType{"string"}, Description: "The city"},
-							},
+							}),
 						},
 					},
 				},
@@ -108,9 +108,9 @@ func TestOlmo3Renderer(t *testing.T) {
 							ID: "call_1",
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: map[string]any{
+								Arguments: testArgs(map[string]any{
 									"location": "San Francisco",
-								},
+								}),
 							},
 						},
 					},
@@ -126,9 +126,9 @@ func TestOlmo3Renderer(t *testing.T) {
 						Parameters: api.ToolFunctionParameters{
 							Type:     "object",
 							Required: []string{"location"},
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"location": {Type: api.PropertyType{"string"}, Description: "The city"},
-							},
+							}),
 						},
 					},
 				},
@@ -172,14 +172,14 @@ func TestOlmo3Renderer(t *testing.T) {
 							ID: "call_1",
 							Function: api.ToolCallFunction{
 								Name:      "get_weather",
-								Arguments: map[string]any{"location": "San Francisco"},
+								Arguments: testArgs(map[string]any{"location": "San Francisco"}),
 							},
 						},
 						{
 							ID: "call_2",
 							Function: api.ToolCallFunction{
 								Name:      "get_weather",
-								Arguments: map[string]any{"location": "New York"},
+								Arguments: testArgs(map[string]any{"location": "New York"}),
 							},
 						},
 					},
@@ -194,9 +194,9 @@ func TestOlmo3Renderer(t *testing.T) {
 						Name: "get_weather",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"location": {Type: api.PropertyType{"string"}},
-							},
+							}),
 						},
 					},
 				},
@@ -227,10 +227,10 @@ func TestOlmo3Renderer(t *testing.T) {
 							ID: "call_1",
 							Function: api.ToolCallFunction{
 								Name: "book_flight",
-								Arguments: map[string]any{
+								Arguments: testArgs(map[string]any{
 									"from": "SFO",
 									"to":   "NYC",
-								},
+								}),
 							},
 						},
 					},
@@ -243,10 +243,10 @@ func TestOlmo3Renderer(t *testing.T) {
 						Name: "book_flight",
 						Parameters: api.ToolFunctionParameters{
 							Type: "object",
-							Properties: map[string]api.ToolProperty{
+							Properties: testPropsMap(map[string]api.ToolProperty{
 								"from": {Type: api.PropertyType{"string"}},
 								"to":   {Type: api.PropertyType{"string"}},
-							},
+							}),
 						},
 					},
 				},

model/renderers/olmo3_think_test.go

@@ -78,7 +78,7 @@ func TestOlmo3ThinkRenderer(t *testing.T) {
 							ID: "call_1",
 							Function: api.ToolCallFunction{
 								Name:      "get_weather",
-								Arguments: map[string]any{"location": "San Francisco"},
+								Arguments: testArgs(map[string]any{"location": "San Francisco"}),
 							},
 						},
 					},

model/renderers/qwen3coder.go

@@ -96,7 +96,7 @@ func (r *Qwen3CoderRenderer) Render(messages []api.Message, tools []api.Tool, _
 				}
 				sb.WriteString("\n<parameters>")
 
-				for name, prop := range tool.Function.Parameters.Properties {
+				for name, prop := range tool.Function.Parameters.Properties.All() {
 					sb.WriteString("\n<parameter>")
 					sb.WriteString("\n<name>" + name + "</name>")
 
@@ -147,7 +147,7 @@ func (r *Qwen3CoderRenderer) Render(messages []api.Message, tools []api.Tool, _
 				}
 				for _, toolCall := range message.ToolCalls {
 					sb.WriteString("\n<tool_call>\n<function=" + toolCall.Function.Name + ">")
-					for name, value := range toolCall.Function.Arguments {
+					for name, value := range toolCall.Function.Arguments.All() {
 						valueStr := formatToolCallArgument(value)
 						sb.WriteString("\n<parameter=" + name + ">\n" + valueStr + "\n</parameter>")
 					}

model/renderers/qwen3coder_test.go

@@ -39,9 +39,9 @@ Hello, how are you?<|im_end|>
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: map[string]any{
+								Arguments: testArgs(map[string]any{
 									"unit": "fahrenheit",
-								},
+								}),
 							},
 						},
 					},
@@ -55,7 +55,7 @@ Hello, how are you?<|im_end|>
 					Description: "Get the current weather in a given location",
 					Parameters: api.ToolFunctionParameters{
 						Required: []string{"unit"},
-						Properties: map[string]api.ToolProperty{
+						Properties: testPropsMap(map[string]api.ToolProperty{
 							"unit": {Type: api.PropertyType{"string"}, Enum: []any{"celsius", "fahrenheit"}, Description: "The unit of temperature"},
 							// TODO(drifkin): add multiple params back once we have predictable
 							// order via some sort of ordered map type (see
@@ -63,7 +63,7 @@ Hello, how are you?<|im_end|>
 							/*
 								"location": {Type: api.PropertyType{"string"}, Description: "The city and state, e.g. San Francisco, CA"},
 							*/
-						},
+						}),
 					},
 				}},
 			},
@@ -140,19 +140,19 @@ That sounds nice! What about New York?<|im_end|>
 				{Role: "system", Content: "You are a helpful assistant with access to tools."},
 				{Role: "user", Content: "call double(1) and triple(2)"},
 				{Role: "assistant", Content: "I'll call double(1) and triple(2) for you.", ToolCalls: []api.ToolCall{
-					{Function: api.ToolCallFunction{Name: "double", Arguments: map[string]any{"number": "1"}}},
+					{Function: api.ToolCallFunction{Name: "double", Arguments: testArgs(map[string]any{"number": "1"})}},
-					{Function: api.ToolCallFunction{Name: "triple", Arguments: map[string]any{"number": "2"}}},
+					{Function: api.ToolCallFunction{Name: "triple", Arguments: testArgs(map[string]any{"number": "2"})}},
 				}},
 				{Role: "tool", Content: "{\"number\": 2}", ToolName: "double"},
 				{Role: "tool", Content: "{\"number\": 6}", ToolName: "triple"},
 			},
 			tools: []api.Tool{
-				{Function: api.ToolFunction{Name: "double", Description: "Double a number", Parameters: api.ToolFunctionParameters{Properties: map[string]api.ToolProperty{
+				{Function: api.ToolFunction{Name: "double", Description: "Double a number", Parameters: api.ToolFunctionParameters{Properties: testPropsMap(map[string]api.ToolProperty{
 					"number": {Type: api.PropertyType{"string"}, Description: "The number to double"},
-				}}}},
+				})}}},
-				{Function: api.ToolFunction{Name: "triple", Description: "Triple a number", Parameters: api.ToolFunctionParameters{Properties: map[string]api.ToolProperty{
+				{Function: api.ToolFunction{Name: "triple", Description: "Triple a number", Parameters: api.ToolFunctionParameters{Properties: testPropsMap(map[string]api.ToolProperty{
 					"number": {Type: api.PropertyType{"string"}, Description: "The number to triple"},
-				}}}},
+				})}}},
 			},
 			expected: `<|im_start|>system
 You are a helpful assistant with access to tools.
@@ -259,9 +259,9 @@ I'll tell you something interesting about cats`,
 				{Role: "assistant", ToolCalls: []api.ToolCall{
 					{Function: api.ToolCallFunction{
 						Name: "echo",
-						Arguments: map[string]any{
+						Arguments: testArgs(map[string]any{
 							"payload": map[string]any{"foo": "bar"},
-						},
+						}),
 					}},
 				}},
 				{Role: "tool", Content: "{\"payload\": {\"foo\": \"bar\"}}", ToolName: "echo"},

model/renderers/qwen3vl_nonthinking_test.go

@@ -337,7 +337,7 @@ Let me analyze this image.`,
 					Role:    "assistant",
 					Content: "I'll check.",
 					ToolCalls: []api.ToolCall{
-						{Function: api.ToolCallFunction{Name: "get-current-weather", Arguments: map[string]any{"location": "Paris", "unit": "celsius"}}},
+						{Function: api.ToolCallFunction{Name: "get-current-weather", Arguments: testArgsOrdered([]orderedArg{{"location", "Paris"}, {"unit", "celsius"}})}},
 					},
 				},
 				{Role: "user", Content: "<tool_response>\n18\n</tool_response>"},
@@ -367,8 +367,8 @@ Thanks!<|im_end|>
 					Role:    "assistant",
 					Content: "before",
 					ToolCalls: []api.ToolCall{
-						{Function: api.ToolCallFunction{Name: "add", Arguments: map[string]any{"a": 2, "b": 3}}},
+						{Function: api.ToolCallFunction{Name: "add", Arguments: testArgsOrdered([]orderedArg{{"a", 2}, {"b", 3}})}},
-						{Function: api.ToolCallFunction{Name: "mul", Arguments: map[string]any{"x": 4, "y": 5}}},
+						{Function: api.ToolCallFunction{Name: "mul", Arguments: testArgsOrdered([]orderedArg{{"x", 4}, {"y", 5}})}},
 					},
 				},
 			},
@@ -387,7 +387,7 @@ before
 			name: "consecutive tool responses grouped",
 			msgs: []api.Message{
 				{Role: "user", Content: "Compute results"},
-				{Role: "assistant", Content: "ok", ToolCalls: []api.ToolCall{{Function: api.ToolCallFunction{Name: "job", Arguments: map[string]any{"n": 1}}}}},
+				{Role: "assistant", Content: "ok", ToolCalls: []api.ToolCall{{Function: api.ToolCallFunction{Name: "job", Arguments: testArgs(map[string]any{"n": 1})}}}},
 				{Role: "tool", Content: "5", ToolName: "job"},
 				{Role: "tool", Content: "6", ToolName: "job"},
 			},
@@ -412,7 +412,7 @@ ok
 			name: "last message is tool then prefill",
 			msgs: []api.Message{
 				{Role: "user", Content: "run"},
-				{Role: "assistant", Content: "ok", ToolCalls: []api.ToolCall{{Function: api.ToolCallFunction{Name: "exec", Arguments: map[string]any{"cmd": "ls"}}}}},
+				{Role: "assistant", Content: "ok", ToolCalls: []api.ToolCall{{Function: api.ToolCallFunction{Name: "exec", Arguments: testArgs(map[string]any{"cmd": "ls"})}}}},
 				{Role: "tool", Content: "done", ToolName: "exec"},
 			},
 			expected: `<|im_start|>user
@@ -447,7 +447,7 @@ done
 					Role:    "assistant",
 					Content: "I'll check.",
 					ToolCalls: []api.ToolCall{
-						{Function: api.ToolCallFunction{Name: "get-current-weather", Arguments: map[string]any{"location": "Paris", "unit": "celsius"}}},
+						{Function: api.ToolCallFunction{Name: "get-current-weather", Arguments: testArgsOrdered([]orderedArg{{"location", "Paris"}, {"unit", "celsius"}})}},
 					},
 				},
 				{Role: "user", Content: "<tool_response>\n18\n</tool_response>"},
@@ -477,7 +477,7 @@ Thanks!<|im_end|>
 					Role:    "assistant",
 					Content: "I'll check.",
 					ToolCalls: []api.ToolCall{
-						{Function: api.ToolCallFunction{Name: "get-current-weather", Arguments: map[string]any{"location": "Paris", "unit": "celsius"}}},
+						{Function: api.ToolCallFunction{Name: "get-current-weather", Arguments: testArgsOrdered([]orderedArg{{"location", "Paris"}, {"unit", "celsius"}})}},
 					},
 				},
 				{Role: "user", Content: "\n\n\n\n<tool_response>\n18\n</tool_response> extra\n\n\n\n\n\n"},

model/renderers/qwen3vl_thinking_test.go

@@ -128,10 +128,10 @@ Speak poetry after the first sentence.</think><think>Speak poetry after the seco
 		// 						{
 		// 							Function: api.ToolCallFunction{
 		// 								Name: "get-current-weather",
-		// 								Arguments: map[string]any{
+		// 								Arguments: testArgs(map[string]any{
 		// 									"location": "New York",
 		// 									"unit":     "fahrenheit",
-		// 								},
+		// 								}),
 		// 							},
 		// 						},
 		// 					},
@@ -148,7 +148,7 @@ Speak poetry after the first sentence.</think><think>Speak poetry after the seco
 		// 						Parameters: api.ToolFunctionParameters{
 		// 							Type:     "object",
 		// 							Required: []string{"location"},
-		// 							Properties: map[string]api.ToolProperty{
+		// 							Properties: testPropsMap(map[string]api.ToolProperty{
 		// 								"location": {
 		// 									Type:        api.PropertyType{"string"},
 		// 									Description: "The city and state, e.g. San Francisco, CA",
@@ -158,7 +158,7 @@ Speak poetry after the first sentence.</think><think>Speak poetry after the seco
 		// 									Enum:        []any{"celsius", "fahrenheit"},
 		// 									Description: "The temperature unit",
 		// 								},
-		// 							},
+		// 							}),
 		// 						},
 		// 					},
 		// 				},
@@ -216,19 +216,19 @@ Speak poetry after the first sentence.</think><think>Speak poetry after the seco
 		// 						{
 		// 							Function: api.ToolCallFunction{
 		// 								Name: "add",
-		// 								Arguments: map[string]any{
+		// 								Arguments: testArgs(map[string]any{
 		// 									"a": 2,
 		// 									"b": 3,
-		// 								},
+		// 								}),
 		// 							},
 		// 						},
 		// 						{
 		// 							Function: api.ToolCallFunction{
 		// 								Name: "multiply",
-		// 								Arguments: map[string]any{
+		// 								Arguments: testArgs(map[string]any{
 		// 									"x": 4,
 		// 									"y": 5,
-		// 								},
+		// 								}),
 		// 							},
 		// 						},
 		// 					},
@@ -257,10 +257,10 @@ Speak poetry after the first sentence.</think><think>Speak poetry after the seco
 		// 						Parameters: api.ToolFunctionParameters{
 		// 							Type:     "object",
 		// 							Required: []string{"a", "b"},
-		// 							Properties: map[string]api.ToolProperty{
+		// 							Properties: testPropsMap(map[string]api.ToolProperty{
 		// 								"a": {Type: api.PropertyType{"integer"}, Description: "First number"},
 		// 								"b": {Type: api.PropertyType{"integer"}, Description: "Second number"},
-		// 							},
+		// 							}),
 		// 						},
 		// 					},
 		// 				},
@@ -272,10 +272,10 @@ Speak poetry after the first sentence.</think><think>Speak poetry after the seco
 		// 						Parameters: api.ToolFunctionParameters{
 		// 							Type:     "object",
 		// 							Required: []string{"x", "y"},
-		// 							Properties: map[string]api.ToolProperty{
+		// 							Properties: testPropsMap(map[string]api.ToolProperty{
 		// 								"x": {Type: api.PropertyType{"integer"}, Description: "First factor"},
 		// 								"y": {Type: api.PropertyType{"integer"}, Description: "Second factor"},
-		// 							},
+		// 							}),
 		// 						},
 		// 					},
 		// 				},

model/renderers/testhelpers_test.go

@@ -0,0 +1,36 @@
+package renderers
+
+import "github.com/ollama/ollama/api"
+
+// testPropsMap creates a ToolPropertiesMap from a map (convenience function for tests, order not preserved)
+func testPropsMap(m map[string]api.ToolProperty) *api.ToolPropertiesMap {
+	props := api.NewToolPropertiesMap()
+	for k, v := range m {
+		props.Set(k, v)
+	}
+	return props
+}
+
+// testArgs creates ToolCallFunctionArguments from a map (convenience function for tests, order not preserved)
+func testArgs(m map[string]any) api.ToolCallFunctionArguments {
+	args := api.NewToolCallFunctionArguments()
+	for k, v := range m {
+		args.Set(k, v)
+	}
+	return args
+}
+
+// orderedArg represents a key-value pair for ordered argument creation
+type orderedArg struct {
+	Key   string
+	Value any
+}
+
+// testArgsOrdered creates ToolCallFunctionArguments with a specific key order
+func testArgsOrdered(pairs []orderedArg) api.ToolCallFunctionArguments {
+	args := api.NewToolCallFunctionArguments()
+	for _, p := range pairs {
+		args.Set(p.Key, p.Value)
+	}
+	return args
+}

openai/openai_test.go

@@ -10,6 +10,20 @@ import (
 	"github.com/ollama/ollama/api"
 )
 
+// testArgs creates ToolCallFunctionArguments from a map (convenience function for tests)
+func testArgs(m map[string]any) api.ToolCallFunctionArguments {
+	args := api.NewToolCallFunctionArguments()
+	for k, v := range m {
+		args.Set(k, v)
+	}
+	return args
+}
+
+// argsComparer provides cmp options for comparing ToolCallFunctionArguments by value
+var argsComparer = cmp.Comparer(func(a, b api.ToolCallFunctionArguments) bool {
+	return cmp.Equal(a.ToMap(), b.ToMap())
+})
+
 const (
 	prefix = `data:image/jpeg;base64,`
 	image  = `iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR42mNk+A8AAQUBAScY42YAAAAASUVORK5CYII=`
@@ -159,9 +173,9 @@ func TestToToolCallsPreservesIDs(t *testing.T) {
 			Function: api.ToolCallFunction{
 				Index: 2,
 				Name:  "get_weather",
-				Arguments: api.ToolCallFunctionArguments{
+				Arguments: testArgs(map[string]any{
 					"location": "Seattle",
-				},
+				}),
 			},
 		},
 		{
@@ -169,9 +183,9 @@ func TestToToolCallsPreservesIDs(t *testing.T) {
 			Function: api.ToolCallFunction{
 				Index: 7,
 				Name:  "get_time",
-				Arguments: api.ToolCallFunctionArguments{
+				Arguments: testArgs(map[string]any{
 					"timezone": "UTC",
-				},
+				}),
 			},
 		},
 	}
@@ -215,7 +229,7 @@ func TestToToolCallsPreservesIDs(t *testing.T) {
 		t.Errorf("tool calls mismatch (-want +got):\n%s", diff)
 	}
 
-	if diff := cmp.Diff(original, toolCalls); diff != "" {
+	if diff := cmp.Diff(original, toolCalls, argsComparer); diff != "" {
 		t.Errorf("input tool calls mutated (-want +got):\n%s", diff)
 	}
 }

openai/responses_test.go

@@ -925,7 +925,7 @@ func TestResponsesStreamConverter_ToolCalls(t *testing.T) {
 					ID: "call_abc",
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: api.ToolCallFunctionArguments{"city": "Paris"},
+						Arguments: testArgs(map[string]any{"city": "Paris"}),
 					},
 				},
 			},
@@ -1800,7 +1800,7 @@ func TestResponsesStreamConverter_FunctionCallStatus(t *testing.T) {
 					ID: "call_abc",
 					Function: api.ToolCallFunction{
 						Name:      "get_weather",
-						Arguments: api.ToolCallFunctionArguments{"city": "Paris"},
+						Arguments: testArgs(map[string]any{"city": "Paris"}),
 					},
 				},
 			},

server/routes_generate_test.go

@@ -22,6 +22,29 @@ import (
 	"github.com/ollama/ollama/ml"
 )
 
+// testPropsMap creates a ToolPropertiesMap from a map (convenience function for tests)
+func testPropsMap(m map[string]api.ToolProperty) *api.ToolPropertiesMap {
+	props := api.NewToolPropertiesMap()
+	for k, v := range m {
+		props.Set(k, v)
+	}
+	return props
+}
+
+// testArgs creates ToolCallFunctionArguments from a map (convenience function for tests)
+func testArgs(m map[string]any) api.ToolCallFunctionArguments {
+	args := api.NewToolCallFunctionArguments()
+	for k, v := range m {
+		args.Set(k, v)
+	}
+	return args
+}
+
+// argsComparer provides cmp options for comparing ToolCallFunctionArguments by value
+var argsComparer = cmp.Comparer(func(a, b api.ToolCallFunctionArguments) bool {
+	return cmp.Equal(a.ToMap(), b.ToMap())
+})
+
 type mockRunner struct {
 	llm.LlamaServer
 
@@ -488,7 +511,7 @@ func TestGenerateChat(t *testing.T) {
 					Parameters: api.ToolFunctionParameters{
 						Type:     "object",
 						Required: []string{"location"},
-						Properties: map[string]api.ToolProperty{
+						Properties: testPropsMap(map[string]api.ToolProperty{
 							"location": {
 								Type:        api.PropertyType{"string"},
 								Description: "The city and state",
@@ -497,7 +520,7 @@ func TestGenerateChat(t *testing.T) {
 								Type: api.PropertyType{"string"},
 								Enum: []any{"celsius", "fahrenheit"},
 							},
-						},
+						}),
 					},
 				},
 			},
@@ -559,15 +582,15 @@ func TestGenerateChat(t *testing.T) {
 		expectedToolCall := api.ToolCall{
 			Function: api.ToolCallFunction{
 				Name: "get_weather",
-				Arguments: api.ToolCallFunctionArguments{
+				Arguments: testArgs(map[string]any{
 					"location": "Seattle, WA",
 					"unit":     "celsius",
-				},
+				}),
 			},
 		}
 
 		expectedToolCall.ID = gotToolCall.ID
-		if diff := cmp.Diff(gotToolCall, expectedToolCall); diff != "" {
+		if diff := cmp.Diff(gotToolCall, expectedToolCall, argsComparer); diff != "" {
 			t.Errorf("tool call mismatch (-got +want):\n%s", diff)
 		}
 	})
@@ -582,7 +605,7 @@ func TestGenerateChat(t *testing.T) {
 					Parameters: api.ToolFunctionParameters{
 						Type:     "object",
 						Required: []string{"location"},
-						Properties: map[string]api.ToolProperty{
+						Properties: testPropsMap(map[string]api.ToolProperty{
 							"location": {
 								Type:        api.PropertyType{"string"},
 								Description: "The city and state",
@@ -591,7 +614,7 @@ func TestGenerateChat(t *testing.T) {
 								Type: api.PropertyType{"string"},
 								Enum: []any{"celsius", "fahrenheit"},
 							},
-						},
+						}),
 					},
 				},
 			},
@@ -688,10 +711,10 @@ func TestGenerateChat(t *testing.T) {
 		expectedToolCall := api.ToolCall{
 			Function: api.ToolCallFunction{
 				Name: "get_weather",
-				Arguments: api.ToolCallFunctionArguments{
+				Arguments: testArgs(map[string]any{
 					"location": "Seattle, WA",
 					"unit":     "celsius",
-				},
+				}),
 			},
 		}
 
@@ -703,7 +726,7 @@ func TestGenerateChat(t *testing.T) {
 		}
 
 		expectedToolCall.ID = finalToolCall.ID
-		if diff := cmp.Diff(finalToolCall, expectedToolCall); diff != "" {
+		if diff := cmp.Diff(finalToolCall, expectedToolCall, argsComparer); diff != "" {
 			t.Errorf("final tool call mismatch (-got +want):\n%s", diff)
 		}
 	})
@@ -716,9 +739,9 @@ func TestGenerateChat(t *testing.T) {
 					Name: "get_weather",
 					Parameters: api.ToolFunctionParameters{
 						Type: "object",
-						Properties: map[string]api.ToolProperty{
+						Properties: testPropsMap(map[string]api.ToolProperty{
 							"location": {Type: api.PropertyType{"string"}},
-						},
+						}),
 					},
 				},
 			},

server/routes_harmony_streaming_test.go

@@ -29,12 +29,12 @@ func getTestTools() []api.Tool {
 				Parameters: api.ToolFunctionParameters{
 					Type:     "object",
 					Required: []string{"location"},
-					Properties: map[string]api.ToolProperty{
+					Properties: testPropsMap(map[string]api.ToolProperty{
 						"location": {
 							Type:        api.PropertyType{"string"},
 							Description: "The city and state, e.g. San Francisco, CA",
 						},
-					},
+					}),
 				},
 			},
 		},
@@ -46,12 +46,12 @@ func getTestTools() []api.Tool {
 				Parameters: api.ToolFunctionParameters{
 					Type:     "object",
 					Required: []string{"expression"},
-					Properties: map[string]api.ToolProperty{
+					Properties: testPropsMap(map[string]api.ToolProperty{
 						"expression": {
 							Type:        api.PropertyType{"string"},
 							Description: "The mathematical expression to calculate",
 						},
-					},
+					}),
 				},
 			},
 		},
@@ -185,9 +185,9 @@ func TestChatHarmonyParserStreamingRealtime(t *testing.T) {
 						{
 							Function: api.ToolCallFunction{
 								Name: "get_weather",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"location": "San Francisco",
-								},
+								}),
 							},
 						},
 					},
@@ -211,9 +211,9 @@ func TestChatHarmonyParserStreamingRealtime(t *testing.T) {
 						{
 							Function: api.ToolCallFunction{
 								Name: "calculate",
-								Arguments: api.ToolCallFunctionArguments{
+								Arguments: testArgs(map[string]any{
 									"expression": "2+2",
-								},
+								}),
 							},
 						},
 					},

template/template.go

@@ -272,8 +272,8 @@ func (t *Template) Execute(w io.Writer, v Values) error {
 	} else if !v.forceLegacy && slices.Contains(vars, "messages") {
 		return t.Template.Execute(w, map[string]any{
 			"System":     system,
-			"Messages":   messages,
+			"Messages":   convertMessagesForTemplate(messages),
-			"Tools":      v.Tools,
+			"Tools":      convertToolsForTemplate(v.Tools),
 			"Response":   "",
 			"Think":      v.Think,
 			"ThinkLevel": v.ThinkLevel,
@@ -373,6 +373,118 @@ func collate(msgs []api.Message) (string, []*api.Message) {
 	return strings.Join(system, "\n\n"), collated
 }
 
+// templateTools is a slice of templateTool that marshals to JSON.
+type templateTools []templateTool
+
+func (t templateTools) String() string {
+	bts, _ := json.Marshal(t)
+	return string(bts)
+}
+
+// templateTool is a template-compatible representation of api.Tool
+// with Properties as a regular map for template ranging.
+type templateTool struct {
+	Type     string               `json:"type"`
+	Items    any                  `json:"items,omitempty"`
+	Function templateToolFunction `json:"function"`
+}
+
+type templateToolFunction struct {
+	Name        string                         `json:"name"`
+	Description string                         `json:"description"`
+	Parameters  templateToolFunctionParameters `json:"parameters"`
+}
+
+type templateToolFunctionParameters struct {
+	Type       string                      `json:"type"`
+	Defs       any                         `json:"$defs,omitempty"`
+	Items      any                         `json:"items,omitempty"`
+	Required   []string                    `json:"required,omitempty"`
+	Properties map[string]api.ToolProperty `json:"properties"`
+}
+
+// templateToolCall is a template-compatible representation of api.ToolCall
+// with Arguments as a regular map for template ranging.
+type templateToolCall struct {
+	ID       string
+	Function templateToolCallFunction
+}
+
+type templateToolCallFunction struct {
+	Index     int
+	Name      string
+	Arguments map[string]any
+}
+
+// templateMessage is a template-compatible representation of api.Message
+// with ToolCalls converted for template use.
+type templateMessage struct {
+	Role       string
+	Content    string
+	Thinking   string
+	Images     []api.ImageData
+	ToolCalls  []templateToolCall
+	ToolName   string
+	ToolCallID string
+}
+
+// convertToolsForTemplate converts Tools to template-compatible format.
+func convertToolsForTemplate(tools api.Tools) templateTools {
+	if tools == nil {
+		return nil
+	}
+	result := make(templateTools, len(tools))
+	for i, tool := range tools {
+		result[i] = templateTool{
+			Type:  tool.Type,
+			Items: tool.Items,
+			Function: templateToolFunction{
+				Name:        tool.Function.Name,
+				Description: tool.Function.Description,
+				Parameters: templateToolFunctionParameters{
+					Type:       tool.Function.Parameters.Type,
+					Defs:       tool.Function.Parameters.Defs,
+					Items:      tool.Function.Parameters.Items,
+					Required:   tool.Function.Parameters.Required,
+					Properties: tool.Function.Parameters.Properties.ToMap(),
+				},
+			},
+		}
+	}
+	return result
+}
+
+// convertMessagesForTemplate converts Messages to template-compatible format.
+func convertMessagesForTemplate(messages []*api.Message) []*templateMessage {
+	if messages == nil {
+		return nil
+	}
+	result := make([]*templateMessage, len(messages))
+	for i, msg := range messages {
+		var toolCalls []templateToolCall
+		for _, tc := range msg.ToolCalls {
+			toolCalls = append(toolCalls, templateToolCall{
+				ID: tc.ID,
+				Function: templateToolCallFunction{
+					Index:     tc.Function.Index,
+					Name:      tc.Function.Name,
+					Arguments: tc.Function.Arguments.ToMap(),
+				},
+			})
+		}
+		result[i] = &templateMessage{
+			Role:       msg.Role,
+			Content:    msg.Content,
+			Thinking:   msg.Thinking,
+			Images:     msg.Images,
+			ToolCalls:  toolCalls,
+			ToolName:   msg.ToolName,
+			ToolCallID: msg.ToolCallID,
+		}
+	}
+	return result
+}
+
 // Identifiers walks the node tree returning any identifiers it finds along the way
 func Identifiers(n parse.Node) ([]string, error) {
 	switch n := n.(type) {

tools/tools.go

@@ -124,16 +124,21 @@ func (p *Parser) parseToolCall() *api.ToolCall {
 		return nil
 	}
 
-	var args map[string]any
+	var argsMap map[string]any
 	if found, i := findArguments(tool, p.buffer); found == nil {
 		return nil
 	} else {
-		args = found
+		argsMap = found
 		if i > end {
 			end = i
 		}
 	}
 
+	args := api.NewToolCallFunctionArguments()
+	for k, v := range argsMap {
+		args.Set(k, v)
+	}
+
 	tc := &api.ToolCall{
 		Function: api.ToolCallFunction{
 			Name:      tool.Function.Name,

tools/tools_test.go

@@ -9,6 +9,29 @@ import (
 	"github.com/ollama/ollama/api"
 )
 
+// argsComparer provides cmp options for comparing ToolCallFunctionArguments by value (order-insensitive)
+var argsComparer = cmp.Comparer(func(a, b api.ToolCallFunctionArguments) bool {
+	return cmp.Equal(a.ToMap(), b.ToMap())
+})
+
+// testPropsMap creates a ToolPropertiesMap from a map (convenience function for tests, order not preserved)
+func testPropsMap(m map[string]api.ToolProperty) *api.ToolPropertiesMap {
+	props := api.NewToolPropertiesMap()
+	for k, v := range m {
+		props.Set(k, v)
+	}
+	return props
+}
+
+// testArgs creates ToolCallFunctionArguments from a map (convenience function for tests, order not preserved)
+func testArgs(m map[string]any) api.ToolCallFunctionArguments {
+	args := api.NewToolCallFunctionArguments()
+	for k, v := range m {
+		args.Set(k, v)
+	}
+	return args
+}
+
 func TestParser(t *testing.T) {
 	qwen, err := template.New("qwen").Parse(`{{if .ToolCalls}}<tool_call>{{range .ToolCalls}}{"name": "{{.Function.Name}}", "arguments": {{.Function.Arguments}}}{{end}}</tool_call>{{end}}`)
 	if err != nil {
@@ -44,7 +67,7 @@ func TestParser(t *testing.T) {
 				Parameters: api.ToolFunctionParameters{
 					Type:     "object",
 					Required: []string{"city"},
-					Properties: map[string]api.ToolProperty{
+					Properties: testPropsMap(map[string]api.ToolProperty{
 						"format": {
 							Type:        api.PropertyType{"string"},
 							Description: "The format to return the temperature in",
@@ -54,7 +77,7 @@ func TestParser(t *testing.T) {
 							Type:        api.PropertyType{"string"},
 							Description: "The city to get the temperature for",
 						},
-					},
+					}),
 				},
 			},
 		},
@@ -65,12 +88,12 @@ func TestParser(t *testing.T) {
 				Description: "Retrieve the current weather conditions for a given location",
 				Parameters: api.ToolFunctionParameters{
 					Type: "object",
-					Properties: map[string]api.ToolProperty{
+					Properties: testPropsMap(map[string]api.ToolProperty{
 						"location": {
 							Type:        api.PropertyType{"string"},
 							Description: "The location to get the weather conditions for",
 						},
-					},
+					}),
 				},
 			},
 		},
@@ -95,12 +118,12 @@ func TestParser(t *testing.T) {
 				Description: "Get the address of a given location",
 				Parameters: api.ToolFunctionParameters{
 					Type: "object",
-					Properties: map[string]api.ToolProperty{
+					Properties: testPropsMap(map[string]api.ToolProperty{
 						"location": {
 							Type:        api.PropertyType{"string"},
 							Description: "The location to get the address for",
 						},
-					},
+					}),
 				},
 			},
 		},
@@ -111,7 +134,7 @@ func TestParser(t *testing.T) {
 				Description: "Add two numbers",
 				Parameters: api.ToolFunctionParameters{
 					Type: "object",
-					Properties: map[string]api.ToolProperty{
+					Properties: testPropsMap(map[string]api.ToolProperty{
 						"a": {
 							Type:        api.PropertyType{"string"},
 							Description: "The first number to add",
@@ -120,7 +143,7 @@ func TestParser(t *testing.T) {
 							Type:        api.PropertyType{"string"},
 							Description: "The second number to add",
 						},
-					},
+					}),
 				},
 			},
 		},
@@ -157,9 +180,9 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index: 0,
 						Name:  "get_conditions",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"location": "San Francisco",
-						},
+						}),
 					},
 				},
 			},
@@ -174,7 +197,7 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index:     0,
 						Name:      "get_conditions",
-						Arguments: api.ToolCallFunctionArguments{},
+						Arguments: api.NewToolCallFunctionArguments(),
 					},
 				},
 			},
@@ -189,9 +212,9 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index: 0,
 						Name:  "get_temperature",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"city": "New York",
-						},
+						}),
 					},
 				},
 			},
@@ -213,19 +236,19 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index: 0,
 						Name:  "get_temperature",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"city":   "London",
 							"format": "fahrenheit",
-						},
+						}),
 					},
 				},
 				{
 					Function: api.ToolCallFunction{
 						Index: 1,
 						Name:  "get_conditions",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"location": "Tokyo",
-						},
+						}),
 					},
 				},
 			},
@@ -240,19 +263,19 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index: 0,
 						Name:  "get_temperature",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"city":   "London",
 							"format": "fahrenheit",
-						},
+						}),
 					},
 				},
 				{
 					Function: api.ToolCallFunction{
 						Index: 1,
 						Name:  "get_conditions",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"location": "Tokyo",
-						},
+						}),
 					},
 				},
 			},
@@ -267,17 +290,17 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index:     0,
 						Name:      "say_hello",
-						Arguments: api.ToolCallFunctionArguments{},
+						Arguments: api.NewToolCallFunctionArguments(),
 					},
 				},
 				{
 					Function: api.ToolCallFunction{
 						Index: 1,
 						Name:  "get_temperature",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"city":   "London",
 							"format": "fahrenheit",
-						},
+						}),
 					},
 				},
 			},
@@ -292,16 +315,16 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index:     0,
 						Name:      "get_conditions",
-						Arguments: api.ToolCallFunctionArguments{},
+						Arguments: api.NewToolCallFunctionArguments(),
 					},
 				},
 				{
 					Function: api.ToolCallFunction{
 						Index: 1,
 						Name:  "get_conditions",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"location": "Tokyo",
-						},
+						}),
 					},
 				},
 			},
@@ -316,9 +339,9 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index: 0,
 						Name:  "get_temperature",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"city": "Tokyo",
-						},
+						}),
 					},
 				},
 			},
@@ -347,9 +370,9 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index: 0,
 						Name:  "get_temperature",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"city": "Tokyo",
-						},
+						}),
 					},
 				},
 			},
@@ -371,9 +394,9 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index: 0,
 						Name:  "get_temperature",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"city": "Tokyo",
-						},
+						}),
 					},
 				},
 			},
@@ -453,18 +476,18 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index: 0,
 						Name:  "get_temperature",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"city": "London",
-						},
+						}),
 					},
 				},
 				{
 					Function: api.ToolCallFunction{
 						Index: 1,
 						Name:  "get_conditions",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"location": "Tokyo",
-						},
+						}),
 					},
 				},
 			},
@@ -486,9 +509,9 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index: 0,
 						Name:  "get_conditions",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"location": "Tokyo",
-						},
+						}),
 					},
 				},
 			},
@@ -528,9 +551,9 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index: 0,
 						Name:  "get_conditions",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"location": "Tokyo",
-						},
+						}),
 					},
 				},
 			},
@@ -563,7 +586,7 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index:     0,
 						Name:      "say_hello_world",
-						Arguments: api.ToolCallFunctionArguments{},
+						Arguments: api.NewToolCallFunctionArguments(),
 					},
 				},
 			},
@@ -591,14 +614,14 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index:     0,
 						Name:      "say_hello_world",
-						Arguments: api.ToolCallFunctionArguments{},
+						Arguments: api.NewToolCallFunctionArguments(),
 					},
 				},
 				{
 					Function: api.ToolCallFunction{
 						Index:     1,
 						Name:      "say_hello",
-						Arguments: api.ToolCallFunctionArguments{},
+						Arguments: api.NewToolCallFunctionArguments(),
 					},
 				},
 			},
@@ -624,14 +647,14 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index:     0,
 						Name:      "say_hello",
-						Arguments: api.ToolCallFunctionArguments{},
+						Arguments: api.NewToolCallFunctionArguments(),
 					},
 				},
 				{
 					Function: api.ToolCallFunction{
 						Index:     1,
 						Name:      "say_hello_world",
-						Arguments: api.ToolCallFunctionArguments{},
+						Arguments: api.NewToolCallFunctionArguments(),
 					},
 				},
 			},
@@ -648,7 +671,7 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index:     0,
 						Name:      "say_hello",
-						Arguments: api.ToolCallFunctionArguments{},
+						Arguments: api.NewToolCallFunctionArguments(),
 					},
 				},
 			},
@@ -665,7 +688,7 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index:     0,
 						Name:      "say_hello_world",
-						Arguments: api.ToolCallFunctionArguments{},
+						Arguments: api.NewToolCallFunctionArguments(),
 					},
 				},
 			},
@@ -687,9 +710,9 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index: 0,
 						Name:  "get_address",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"location": "London",
-						},
+						}),
 					},
 				},
 			},
@@ -706,9 +729,9 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index: 0,
 						Name:  "get_address",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"location": "London",
-						},
+						}),
 					},
 				},
 			},
@@ -725,10 +748,10 @@ func TestParser(t *testing.T) {
 					Function: api.ToolCallFunction{
 						Index: 0,
 						Name:  "add",
-						Arguments: api.ToolCallFunctionArguments{
+						Arguments: testArgs(map[string]any{
 							"a": "5",
 							"b": "10",
-						},
+						}),
 					},
 				},
 			},
@@ -756,7 +779,7 @@ func TestParser(t *testing.T) {
 			}
 
 			for i, want := range tt.calls {
-				if diff := cmp.Diff(calls[i], want); diff != "" {
+				if diff := cmp.Diff(calls[i], want, argsComparer); diff != "" {
 					t.Errorf("Tool call %d mismatch (-got +want):\n%s", i, diff)
 				}
 			}
@@ -1316,7 +1339,7 @@ func TestFindArguments(t *testing.T) {
 			got, _ := findArguments(&api.Tool{Function: api.ToolFunction{Name: tt.tool}}, tt.buffer)
 
 			if diff := cmp.Diff(got, tt.want); diff != "" {
-				t.Errorf("scanArguments() args mismatch (-got +want):\n%s", diff)
+				t.Errorf("findArguments() args mismatch (-got +want):\n%s", diff)
 			}
 		})
 	}