skills: add registry reference check and working directory env var

- Add check for registry references without digest in loadSkillsFromRefs
- Fix IsLocalSkillPath to not treat registry refs as local paths
- Inject OLLAMA_WORKING_DIR env var so skill scripts can access the
  directory where 'ollama run' was called from

cmd/skills.go

@@ -140,6 +140,13 @@ func loadSkillsFromRefs(refs []api.SkillRef) (*skillCatalog, error) {
 
 			skillDir = path
 		} else if ref.Name != "" {
+			// Check if this is a local path or a registry reference
+			if !server.IsLocalSkillPath(ref.Name) {
+				// Registry reference without a digest - skill needs to be pulled first
+				// This happens when an agent references a skill that hasn't been bundled
+				return nil, fmt.Errorf("skill %q is a registry reference but has no digest - the agent may need to be recreated or the skill pulled separately", ref.Name)
+			}
+
 			// Local path - resolve it
 			skillPath := ref.Name
 			if strings.HasPrefix(skillPath, "~") {
@@ -486,6 +493,14 @@ func runSkillScript(skillDir, command string) (string, error) {
 	cmd := exec.CommandContext(ctx, "sh", "-c", command)
 	cmd.Dir = absSkillDir
 
+	// Inject the current working directory (where ollama run was called from)
+	// as an environment variable so scripts can reference files in that directory
+	workingDir, err := os.Getwd()
+	if err != nil {
+		return "", fmt.Errorf("failed to get working directory: %w", err)
+	}
+	cmd.Env = append(os.Environ(), "OLLAMA_WORKING_DIR="+workingDir)
+
 	// Capture both stdout and stderr
 	var stdout, stderr bytes.Buffer
 	cmd.Stdout = &stdout

server/skill.go

@@ -250,13 +250,14 @@ func CreateSkillLayer(skillDir string) (Layer, error) {
 }
 
 // IsLocalSkillPath checks if a skill reference looks like a local path.
+// Local paths are explicitly prefixed with /, ./, ../, or ~.
+// Registry references like "skill/calculator:1.0.0" should NOT be treated as local paths.
 func IsLocalSkillPath(name string) bool {
-	// Local paths start with /, ./, or contain path separators
+	// Local paths are explicitly indicated by path prefixes
 	return strings.HasPrefix(name, "/") ||
 		strings.HasPrefix(name, "./") ||
 		strings.HasPrefix(name, "../") ||
-		strings.HasPrefix(name, "~") ||
-		strings.Contains(name, string(os.PathSeparator))
+		strings.HasPrefix(name, "~")
 }
 
 // SkillNamespace is the namespace used for standalone skills in the registry.