diff --git a/api/types.go b/api/types.go
index e2c63b62..0f99de18 100644
--- a/api/types.go
+++ b/api/types.go
@@ -225,20 +225,68 @@ func (pt PropertyType) String() string {
 	return fmt.Sprintf("%v", []string(pt))
 }
 
+type ToolProperty struct {
+	AnyOf       []ToolProperty `json:"anyOf,omitempty"`
+	Type        PropertyType   `json:"type"`
+	Items       any            `json:"items,omitempty"`
+	Description string         `json:"description"`
+	Enum        []any          `json:"enum,omitempty"`
+}
+
+// ToTypeScriptType converts a ToolProperty to a TypeScript type string
+func (tp ToolProperty) ToTypeScriptType() string {
+	if len(tp.AnyOf) > 0 {
+		var types []string
+		for _, anyOf := range tp.AnyOf {
+			types = append(types, anyOf.ToTypeScriptType())
+		}
+		return strings.Join(types, " | ")
+	}
+
+	if len(tp.Type) == 0 {
+		return "any"
+	}
+
+	if len(tp.Type) == 1 {
+		return mapToTypeScriptType(tp.Type[0])
+	}
+
+	var types []string
+	for _, t := range tp.Type {
+		types = append(types, mapToTypeScriptType(t))
+	}
+	return strings.Join(types, " | ")
+}
+
+// mapToTypeScriptType maps JSON Schema types to TypeScript types
+func mapToTypeScriptType(jsonType string) string {
+	switch jsonType {
+	case "string":
+		return "string"
+	case "number", "integer":
+		return "number"
+	case "boolean":
+		return "boolean"
+	case "array":
+		return "any[]"
+	case "object":
+		return "Record<string, any>"
+	case "null":
+		return "null"
+	default:
+		return "any"
+	}
+}
+
 type ToolFunction struct {
 	Name        string `json:"name"`
 	Description string `json:"description"`
 	Parameters  struct {
-		Type       string   `json:"type"`
-		Defs       any      `json:"$defs,omitempty"`
-		Items      any      `json:"items,omitempty"`
-		Required   []string `json:"required"`
-		Properties map[string]struct {
-			Type        PropertyType `json:"type"`
-			Items       any          `json:"items,omitempty"`
-			Description string       `json:"description"`
-			Enum        []any        `json:"enum,omitempty"`
-		} `json:"properties"`
+		Type       string                  `json:"type"`
+		Defs       any                     `json:"$defs,omitempty"`
+		Items      any                     `json:"items,omitempty"`
+		Required   []string                `json:"required"`
+		Properties map[string]ToolProperty `json:"properties"`
 	} `json:"parameters"`
 }
 
diff --git a/api/types_typescript_test.go b/api/types_typescript_test.go
new file mode 100644
index 00000000..9902c5be
--- /dev/null
+++ b/api/types_typescript_test.go
@@ -0,0 +1,142 @@
+package api
+
+import (
+	"testing"
+)
+
+func TestToolParameterToTypeScriptType(t *testing.T) {
+	tests := []struct {
+		name     string
+		param    ToolProperty
+		expected string
+	}{
+		{
+			name: "single string type",
+			param: ToolProperty{
+				Type: PropertyType{"string"},
+			},
+			expected: "string",
+		},
+		{
+			name: "single number type",
+			param: ToolProperty{
+				Type: PropertyType{"number"},
+			},
+			expected: "number",
+		},
+		{
+			name: "integer maps to number",
+			param: ToolProperty{
+				Type: PropertyType{"integer"},
+			},
+			expected: "number",
+		},
+		{
+			name: "boolean type",
+			param: ToolProperty{
+				Type: PropertyType{"boolean"},
+			},
+			expected: "boolean",
+		},
+		{
+			name: "array type",
+			param: ToolProperty{
+				Type: PropertyType{"array"},
+			},
+			expected: "any[]",
+		},
+		{
+			name: "object type",
+			param: ToolProperty{
+				Type: PropertyType{"object"},
+			},
+			expected: "Record<string, any>",
+		},
+		{
+			name: "null type",
+			param: ToolProperty{
+				Type: PropertyType{"null"},
+			},
+			expected: "null",
+		},
+		{
+			name: "multiple types as union",
+			param: ToolProperty{
+				Type: PropertyType{"string", "number"},
+			},
+			expected: "string | number",
+		},
+		{
+			name: "string or null union",
+			param: ToolProperty{
+				Type: PropertyType{"string", "null"},
+			},
+			expected: "string | null",
+		},
+		{
+			name: "anyOf with single types",
+			param: ToolProperty{
+				AnyOf: []ToolProperty{
+					{Type: PropertyType{"string"}},
+					{Type: PropertyType{"number"}},
+				},
+			},
+			expected: "string | number",
+		},
+		{
+			name: "anyOf with multiple types in each branch",
+			param: ToolProperty{
+				AnyOf: []ToolProperty{
+					{Type: PropertyType{"string", "null"}},
+					{Type: PropertyType{"number"}},
+				},
+			},
+			expected: "string | null | number",
+		},
+		{
+			name: "nested anyOf",
+			param: ToolProperty{
+				AnyOf: []ToolProperty{
+					{Type: PropertyType{"boolean"}},
+					{
+						AnyOf: []ToolProperty{
+							{Type: PropertyType{"string"}},
+							{Type: PropertyType{"number"}},
+						},
+					},
+				},
+			},
+			expected: "boolean | string | number",
+		},
+		{
+			name: "empty type returns any",
+			param: ToolProperty{
+				Type: PropertyType{},
+			},
+			expected: "any",
+		},
+		{
+			name: "unknown type maps to any",
+			param: ToolProperty{
+				Type: PropertyType{"unknown_type"},
+			},
+			expected: "any",
+		},
+		{
+			name: "multiple types including array",
+			param: ToolProperty{
+				Type: PropertyType{"string", "array", "null"},
+			},
+			expected: "string | any[] | null",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			result := tt.param.ToTypeScriptType()
+			if result != tt.expected {
+				t.Errorf("ToTypeScriptType() = %q, want %q", result, tt.expected)
+			}
+		})
+	}
+}
diff --git a/openai/openai_test.go b/openai/openai_test.go
index a24093ad..471b4737 100644
--- a/openai/openai_test.go
+++ b/openai/openai_test.go
@@ -280,25 +280,15 @@ func TestChatMiddleware(t *testing.T) {
 							Name:        "get_weather",
 							Description: "Get the current weather",
 							Parameters: struct {
-								Type       string   `json:"type"`
-								Defs       any      `json:"$defs,omitempty"`
-								Items      any      `json:"items,omitempty"`
-								Required   []string `json:"required"`
-								Properties map[string]struct {
-									Type        api.PropertyType `json:"type"`
-									Items       any              `json:"items,omitempty"`
-									Description string           `json:"description"`
-									Enum        []any            `json:"enum,omitempty"`
-								} `json:"properties"`
+								Type       string                      `json:"type"`
+								Defs       any                         `json:"$defs,omitempty"`
+								Items      any                         `json:"items,omitempty"`
+								Required   []string                    `json:"required"`
+								Properties map[string]api.ToolProperty `json:"properties"`
 							}{
 								Type:     "object",
 								Required: []string{"location"},
-								Properties: map[string]struct {
-									Type        api.PropertyType `json:"type"`
-									Items       any              `json:"items,omitempty"`
-									Description string           `json:"description"`
-									Enum        []any            `json:"enum,omitempty"`
-								}{
+								Properties: map[string]api.ToolProperty{
 									"location": {
 										Type:        api.PropertyType{"string"},
 										Description: "The city and state",
diff --git a/server/routes_generate_test.go b/server/routes_generate_test.go
index 477d6b81..506071ed 100644
--- a/server/routes_generate_test.go
+++ b/server/routes_generate_test.go
@@ -388,25 +388,15 @@ func TestGenerateChat(t *testing.T) {
 					Name:        "get_weather",
 					Description: "Get the current weather",
 					Parameters: struct {
-						Type       string   `json:"type"`
-						Defs       any      `json:"$defs,omitempty"`
-						Items      any      `json:"items,omitempty"`
-						Required   []string `json:"required"`
-						Properties map[string]struct {
-							Type        api.PropertyType `json:"type"`
-							Items       any              `json:"items,omitempty"`
-							Description string           `json:"description"`
-							Enum        []any            `json:"enum,omitempty"`
-						} `json:"properties"`
+						Type       string                      `json:"type"`
+						Defs       any                         `json:"$defs,omitempty"`
+						Items      any                         `json:"items,omitempty"`
+						Required   []string                    `json:"required"`
+						Properties map[string]api.ToolProperty `json:"properties"`
 					}{
 						Type:     "object",
 						Required: []string{"location"},
-						Properties: map[string]struct {
-							Type        api.PropertyType `json:"type"`
-							Items       any              `json:"items,omitempty"`
-							Description string           `json:"description"`
-							Enum        []any            `json:"enum,omitempty"`
-						}{
+						Properties: map[string]api.ToolProperty{
 							"location": {
 								Type:        api.PropertyType{"string"},
 								Description: "The city and state",
@@ -489,25 +479,15 @@ func TestGenerateChat(t *testing.T) {
 					Name:        "get_weather",
 					Description: "Get the current weather",
 					Parameters: struct {
-						Type       string   `json:"type"`
-						Defs       any      `json:"$defs,omitempty"`
-						Items      any      `json:"items,omitempty"`
-						Required   []string `json:"required"`
-						Properties map[string]struct {
-							Type        api.PropertyType `json:"type"`
-							Items       any              `json:"items,omitempty"`
-							Description string           `json:"description"`
-							Enum        []any            `json:"enum,omitempty"`
-						} `json:"properties"`
+						Type       string                      `json:"type"`
+						Defs       any                         `json:"$defs,omitempty"`
+						Items      any                         `json:"items,omitempty"`
+						Required   []string                    `json:"required"`
+						Properties map[string]api.ToolProperty `json:"properties"`
 					}{
 						Type:     "object",
 						Required: []string{"location"},
-						Properties: map[string]struct {
-							Type        api.PropertyType `json:"type"`
-							Items       any              `json:"items,omitempty"`
-							Description string           `json:"description"`
-							Enum        []any            `json:"enum,omitempty"`
-						}{
+						Properties: map[string]api.ToolProperty{
 							"location": {
 								Type:        api.PropertyType{"string"},
 								Description: "The city and state",
diff --git a/server/routes_harmony_streaming_test.go b/server/routes_harmony_streaming_test.go
index 503cb4d7..1b86f84c 100644
--- a/server/routes_harmony_streaming_test.go
+++ b/server/routes_harmony_streaming_test.go
@@ -27,25 +27,15 @@ func getTestTools() []api.Tool {
 				Name:        "get_weather",
 				Description: "Get the current weather in a given location",
 				Parameters: struct {
-					Type       string   `json:"type"`
-					Defs       any      `json:"$defs,omitempty"`
-					Items      any      `json:"items,omitempty"`
-					Required   []string `json:"required"`
-					Properties map[string]struct {
-						Type        api.PropertyType `json:"type"`
-						Items       any              `json:"items,omitempty"`
-						Description string           `json:"description"`
-						Enum        []any            `json:"enum,omitempty"`
-					} `json:"properties"`
+					Type       string                      `json:"type"`
+					Defs       any                         `json:"$defs,omitempty"`
+					Items      any                         `json:"items,omitempty"`
+					Required   []string                    `json:"required"`
+					Properties map[string]api.ToolProperty `json:"properties"`
 				}{
 					Type:     "object",
 					Required: []string{"location"},
-					Properties: map[string]struct {
-						Type        api.PropertyType `json:"type"`
-						Items       any              `json:"items,omitempty"`
-						Description string           `json:"description"`
-						Enum        []any            `json:"enum,omitempty"`
-					}{
+					Properties: map[string]api.ToolProperty{
 						"location": {
 							Type:        api.PropertyType{"string"},
 							Description: "The city and state, e.g. San Francisco, CA",
@@ -60,25 +50,15 @@ func getTestTools() []api.Tool {
 				Name:        "calculate",
 				Description: "Calculate a mathematical expression",
 				Parameters: struct {
-					Type       string   `json:"type"`
-					Defs       any      `json:"$defs,omitempty"`
-					Items      any      `json:"items,omitempty"`
-					Required   []string `json:"required"`
-					Properties map[string]struct {
-						Type        api.PropertyType `json:"type"`
-						Items       any              `json:"items,omitempty"`
-						Description string           `json:"description"`
-						Enum        []any            `json:"enum,omitempty"`
-					} `json:"properties"`
+					Type       string                      `json:"type"`
+					Defs       any                         `json:"$defs,omitempty"`
+					Items      any                         `json:"items,omitempty"`
+					Required   []string                    `json:"required"`
+					Properties map[string]api.ToolProperty `json:"properties"`
 				}{
 					Type:     "object",
 					Required: []string{"expression"},
-					Properties: map[string]struct {
-						Type        api.PropertyType `json:"type"`
-						Items       any              `json:"items,omitempty"`
-						Description string           `json:"description"`
-						Enum        []any            `json:"enum,omitempty"`
-					}{
+					Properties: map[string]api.ToolProperty{
 						"expression": {
 							Type:        api.PropertyType{"string"},
 							Description: "The mathematical expression to calculate",
diff --git a/template/template.go b/template/template.go
index bfd02a92..f2775b91 100644
--- a/template/template.go
+++ b/template/template.go
@@ -127,6 +127,16 @@ var funcs = template.FuncMap{
 		// Default format is YYYY-MM-DD
 		return time.Now().Format("2006-01-02")
 	},
+	"toTypeScriptType": func(v any) string {
+		if param, ok := v.(api.ToolProperty); ok {
+			return param.ToTypeScriptType()
+		}
+		// Handle pointer case
+		if param, ok := v.(*api.ToolProperty); ok && param != nil {
+			return param.ToTypeScriptType()
+		}
+		return "any"
+	},
 }
 
 func Parse(s string) (*Template, error) {
diff --git a/tools/tools_test.go b/tools/tools_test.go
index a0f7b6b0..7f00be20 100644
--- a/tools/tools_test.go
+++ b/tools/tools_test.go
@@ -41,25 +41,15 @@ func TestParser(t *testing.T) {
 				Name:        "get_temperature",
 				Description: "Retrieve the temperature for a given location",
 				Parameters: struct {
-					Type       string   `json:"type"`
-					Defs       any      `json:"$defs,omitempty"`
-					Items      any      `json:"items,omitempty"`
-					Required   []string `json:"required"`
-					Properties map[string]struct {
-						Type        api.PropertyType `json:"type"`
-						Items       any              `json:"items,omitempty"`
-						Description string           `json:"description"`
-						Enum        []any            `json:"enum,omitempty"`
-					} `json:"properties"`
+					Type       string                      `json:"type"`
+					Defs       any                         `json:"$defs,omitempty"`
+					Items      any                         `json:"items,omitempty"`
+					Required   []string                    `json:"required"`
+					Properties map[string]api.ToolProperty `json:"properties"`
 				}{
 					Type:     "object",
 					Required: []string{"city"},
-					Properties: map[string]struct {
-						Type        api.PropertyType `json:"type"`
-						Items       any              `json:"items,omitempty"`
-						Description string           `json:"description"`
-						Enum        []any            `json:"enum,omitempty"`
-					}{
+					Properties: map[string]api.ToolProperty{
 						"format": {
 							Type:        api.PropertyType{"string"},
 							Description: "The format to return the temperature in",
@@ -79,24 +69,14 @@ func TestParser(t *testing.T) {
 				Name:        "get_conditions",
 				Description: "Retrieve the current weather conditions for a given location",
 				Parameters: struct {
-					Type       string   `json:"type"`
-					Defs       any      `json:"$defs,omitempty"`
-					Items      any      `json:"items,omitempty"`
-					Required   []string `json:"required"`
-					Properties map[string]struct {
-						Type        api.PropertyType `json:"type"`
-						Items       any              `json:"items,omitempty"`
-						Description string           `json:"description"`
-						Enum        []any            `json:"enum,omitempty"`
-					} `json:"properties"`
+					Type       string                      `json:"type"`
+					Defs       any                         `json:"$defs,omitempty"`
+					Items      any                         `json:"items,omitempty"`
+					Required   []string                    `json:"required"`
+					Properties map[string]api.ToolProperty `json:"properties"`
 				}{
 					Type: "object",
-					Properties: map[string]struct {
-						Type        api.PropertyType `json:"type"`
-						Items       any              `json:"items,omitempty"`
-						Description string           `json:"description"`
-						Enum        []any            `json:"enum,omitempty"`
-					}{
+					Properties: map[string]api.ToolProperty{
 						"location": {
 							Type:        api.PropertyType{"string"},
 							Description: "The location to get the weather conditions for",
@@ -125,24 +105,14 @@ func TestParser(t *testing.T) {
 				Name:        "get_address",
 				Description: "Get the address of a given location",
 				Parameters: struct {
-					Type       string   `json:"type"`
-					Defs       any      `json:"$defs,omitempty"`
-					Items      any      `json:"items,omitempty"`
-					Required   []string `json:"required"`
-					Properties map[string]struct {
-						Type        api.PropertyType `json:"type"`
-						Items       any              `json:"items,omitempty"`
-						Description string           `json:"description"`
-						Enum        []any            `json:"enum,omitempty"`
-					} `json:"properties"`
+					Type       string                      `json:"type"`
+					Defs       any                         `json:"$defs,omitempty"`
+					Items      any                         `json:"items,omitempty"`
+					Required   []string                    `json:"required"`
+					Properties map[string]api.ToolProperty `json:"properties"`
 				}{
 					Type: "object",
-					Properties: map[string]struct {
-						Type        api.PropertyType `json:"type"`
-						Items       any              `json:"items,omitempty"`
-						Description string           `json:"description"`
-						Enum        []any            `json:"enum,omitempty"`
-					}{
+					Properties: map[string]api.ToolProperty{
 						"location": {
 							Type:        api.PropertyType{"string"},
 							Description: "The location to get the address for",
@@ -157,24 +127,14 @@ func TestParser(t *testing.T) {
 				Name:        "add",
 				Description: "Add two numbers",
 				Parameters: struct {
-					Type       string   `json:"type"`
-					Defs       any      `json:"$defs,omitempty"`
-					Items      any      `json:"items,omitempty"`
-					Required   []string `json:"required"`
-					Properties map[string]struct {
-						Type        api.PropertyType `json:"type"`
-						Items       any              `json:"items,omitempty"`
-						Description string           `json:"description"`
-						Enum        []any            `json:"enum,omitempty"`
-					} `json:"properties"`
+					Type       string                      `json:"type"`
+					Defs       any                         `json:"$defs,omitempty"`
+					Items      any                         `json:"items,omitempty"`
+					Required   []string                    `json:"required"`
+					Properties map[string]api.ToolProperty `json:"properties"`
 				}{
 					Type: "object",
-					Properties: map[string]struct {
-						Type        api.PropertyType `json:"type"`
-						Items       any              `json:"items,omitempty"`
-						Description string           `json:"description"`
-						Enum        []any            `json:"enum,omitempty"`
-					}{
+					Properties: map[string]api.ToolProperty{
 						"a": {
 							Type:        api.PropertyType{"string"},
 							Description: "The first number to add",