diff --git a/openai/openai.go b/openai/openai.go
index 6a1b54928..9d0f95e0c 100644
--- a/openai/openai.go
+++ b/openai/openai.go
@@ -156,7 +156,19 @@ func (tc *ToolChoice) IsRequired() bool {
 
 // IsAuto returns true if tool_choice is "auto" or not specified
 func (tc *ToolChoice) IsAuto() bool {
-	return tc == nil || tc.Mode == "" || tc.Mode == "auto"
+	if tc == nil {
+		return true
+	}
+	// If there's an object, check if it's allowed_tools with auto mode
+	if tc.Object != nil {
+		// allowed_tools with "auto" mode is still considered auto
+		if tc.Object.Type == "allowed_tools" && (tc.Object.Mode == "" || tc.Object.Mode == "auto") {
+			return true
+		}
+		// Any other object (forced function, allowed_tools with required) is not auto
+		return false
+	}
+	return tc.Mode == "" || tc.Mode == "auto"
 }
 
 // IsForcedFunction returns true if a specific function is forced
diff --git a/openai/openai_test.go b/openai/openai_test.go
index b551058e6..850a017d8 100644
--- a/openai/openai_test.go
+++ b/openai/openai_test.go
@@ -646,7 +646,7 @@ func TestApplyToolChoice(t *testing.T) {
 				Description: "Get weather",
 				Parameters: api.ToolFunctionParameters{
 					Type: "object",
-					Properties: map[string]api.Property{
+					Properties: map[string]api.ToolProperty{
 						"location": {Type: []string{"string"}},
 					},
 					Required: []string{"location"},
@@ -660,7 +660,7 @@ func TestApplyToolChoice(t *testing.T) {
 				Description: "Search the web",
 				Parameters: api.ToolFunctionParameters{
 					Type: "object",
-					Properties: map[string]api.Property{
+					Properties: map[string]api.ToolProperty{
 						"query": {Type: []string{"string"}},
 					},
 					Required: []string{"query"},
@@ -806,7 +806,7 @@ func TestFromChatRequest_WithToolChoice(t *testing.T) {
 				Description: "Get weather",
 				Parameters: api.ToolFunctionParameters{
 					Type: "object",
-					Properties: map[string]api.Property{
+					Properties: map[string]api.ToolProperty{
 						"location": {Type: []string{"string"}},
 					},
 				},
@@ -819,7 +819,7 @@ func TestFromChatRequest_WithToolChoice(t *testing.T) {
 				Description: "Search",
 				Parameters: api.ToolFunctionParameters{
 					Type: "object",
-					Properties: map[string]api.Property{
+					Properties: map[string]api.ToolProperty{
 						"query": {Type: []string{"string"}},
 					},
 				},