Add ToolType enum for type-safe tool definitions

- Created ToolType enum with Function value
- Updated all tool type definitions to use ToolType.Function
- Exported ToolType from SDK index
- Updated all examples to use the enum
- Updated all tests to use the enum
- Improved type safety across the codebase

This provides a cleaner API where users can import ToolType
instead of using string literals with "as const".

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

Author: Matt Apperson

examples/tools-example.ts

@@ -19,7 +19,7 @@
  *   - Context includes: numberOfTurns, messageHistory, model/models
  */
 
-import { OpenRouter } from "../src/index.js";
+import { OpenRouter, ToolType } from "../src/index.js";
 import { z } from "zod/v4";
 import * as dotenv from "dotenv";
 
@@ -38,7 +38,7 @@ async function basicToolExample() {
   console.log("\n=== Example 1: Basic Tool with Execute Function ===\n");
 
   const weatherTool = {
-    type: "function" as const,
+    type: ToolType.Function,
     function: {
       name: "get_weather",
       description: "Get current weather for a location",
@@ -91,7 +91,7 @@ async function generatorToolExample() {
   console.log("\n=== Example 2: Generator Tool with Preliminary Results ===\n");
 
   const processingTool = {
-    type: "function" as const,
+    type: ToolType.Function,
     function: {
       name: "process_data",
       description: "Process data with progress updates",
@@ -162,7 +162,7 @@ async function manualToolExample() {
   console.log("\n=== Example 3: Manual Tool Execution ===\n");
 
   const calculatorTool = {
-    type: "function" as const,
+    type: ToolType.Function,
     function: {
       name: "calculate",
       description: "Perform mathematical calculations",
@@ -216,7 +216,7 @@ async function streamingToolCallsExample() {
   console.log("\n=== Example 4: Streaming Tool Calls ===\n");
 
   const searchTool = {
-    type: "function" as const,
+    type: ToolType.Function,
     function: {
       name: "search",
       description: "Search for information",
@@ -262,7 +262,7 @@ async function multipleToolsExample() {
 
   const tools = [
     {
-      type: "function" as const,
+      type: ToolType.Function,
       function: {
         name: "get_time",
         description: "Get current time",
@@ -282,7 +282,7 @@ async function multipleToolsExample() {
       },
     },
     {
-      type: "function" as const,
+      type: ToolType.Function,
       function: {
         name: "get_weather",
         description: "Get weather information",

src/index.ts

@@ -10,6 +10,7 @@ export type { Fetcher, HTTPClientOptions } from "./lib/http.js";
 export { ResponseWrapper } from "./lib/response-wrapper.js";
 export type { GetResponseOptions } from "./lib/response-wrapper.js";
 export { ReusableReadableStream } from "./lib/reusable-stream.js";
+export { ToolType } from "./lib/tool-types.js";
 export type {
   EnhancedTool,
   ToolWithExecute,

src/lib/tool-types.ts

@@ -1,6 +1,13 @@
 import { z, ZodType, ZodObject, ZodRawShape } from "zod";
 import * as models from "../models/index.js";
 
+/**
+ * Tool type enum for enhanced tools
+ */
+export enum ToolType {
+  Function = "function",
+}
+
 /**
  * Turn context passed to tool execute functions
  * Contains information about the current conversation state
@@ -73,7 +80,7 @@ export type ToolWithExecute<
   TInput extends ZodObject<ZodRawShape> = ZodObject<ZodRawShape>,
   TOutput extends ZodType = ZodType<any>
 > = {
-  type: "function";
+  type: ToolType.Function;
   function: ToolFunctionWithExecute<TInput, TOutput>;
 };
 
@@ -84,7 +91,7 @@ export type ToolWithGenerator<
   TInput extends ZodObject<ZodRawShape> = ZodObject<ZodRawShape>,
   TEvent extends ZodType = ZodType<any>
 > = {
-  type: "function";
+  type: ToolType.Function;
   function: ToolFunctionWithGenerator<TInput, TEvent>;
 };
 
@@ -95,7 +102,7 @@ export type ManualTool<
   TInput extends ZodObject<ZodRawShape> = ZodObject<ZodRawShape>,
   TOutput extends ZodType = ZodType<any>
 > = {
-  type: "function";
+  type: ToolType.Function;
   function: ManualToolFunction<TInput, TOutput>;
 };
 

tests/e2e/getResponse-tools.test.ts

@@ -1,5 +1,5 @@
 import { describe, it, expect, beforeAll } from "vitest";
-import { OpenRouter } from "../../src/index.js";
+import { OpenRouter, ToolType } from "../../src/index.js";
 import { z } from "zod";
 import { toJSONSchema } from "zod/v4";
 import * as dotenv from "dotenv";
@@ -66,7 +66,7 @@ describe("Enhanced Tool Support for getResponse", () => {
   describe("Tool Definition", () => {
     it("should define tool with inputSchema", async () => {
       const weatherTool = {
-        type: "function" as const,
+        type: ToolType.Function,
         function: {
           name: "get_weather",
           description: "Get current temperature for a given location.",
@@ -124,7 +124,7 @@ describe("Enhanced Tool Support for getResponse", () => {
   describe("Regular Tool Execution", () => {
     it("should execute tool with valid input", async () => {
       const addTool = {
-        type: "function" as const,
+        type: ToolType.Function,
         function: {
           name: "add_numbers",
           description: "Add two numbers together",
@@ -165,7 +165,7 @@ describe("Enhanced Tool Support for getResponse", () => {
 
     it("should handle execution errors gracefully", async () => {
       const errorTool = {
-        type: "function" as const,
+        type: ToolType.Function,
         function: {
           name: "error_tool",
           inputSchema: z.object({}),
@@ -200,7 +200,7 @@ describe("Enhanced Tool Support for getResponse", () => {
       });
 
       const generatorTool = {
-        type: "function" as const,
+        type: ToolType.Function,
         function: {
           name: "get_weather_with_updates",
           description: "Get weather with streaming updates",
@@ -239,7 +239,7 @@ describe("Enhanced Tool Support for getResponse", () => {
 
     it("should send only final (last) yield to model", async () => {
       const generatorTool = {
-        type: "function" as const,
+        type: ToolType.Function,
         function: {
           name: "process_data",
           inputSchema: z.object({ data: z.string() }),
@@ -306,7 +306,7 @@ describe("Enhanced Tool Support for getResponse", () => {
       const preliminaryResults: any[] = [];
 
       const generatorTool = {
-        type: "function" as const,
+        type: ToolType.Function,
         function: {
           name: "streaming_tool",
           inputSchema: z.object({ input: z.string() }),
@@ -339,7 +339,7 @@ describe("Enhanced Tool Support for getResponse", () => {
   describe("Manual Tool Execution", () => {
     it("should define tool without execute function", () => {
       const manualTool = {
-        type: "function" as const,
+        type: ToolType.Function,
         function: {
           name: "manual_tool",
           description: "A tool that requires manual handling",
@@ -361,7 +361,7 @@ describe("Enhanced Tool Support for getResponse", () => {
     it.skip("should send tool call to API and receive tool call response", async () => {
       // This test requires actual API integration which we'll implement
       const weatherTool = {
-        type: "function" as const,
+        type: ToolType.Function,
         function: {
           name: "get_weather",
           description: "Get the current weather for a location",
@@ -399,7 +399,7 @@ describe("Enhanced Tool Support for getResponse", () => {
     it.skip("should handle multi-turn conversation with tool execution", async () => {
       // This will test the full loop: request -> tool call -> execute -> send result -> final response
       const calculatorTool = {
-        type: "function" as const,
+        type: ToolType.Function,
         function: {
           name: "calculate",
           description: "Perform a mathematical calculation",
@@ -490,7 +490,7 @@ describe("Enhanced Tool Support for getResponse", () => {
   describe("Type Safety", () => {
     it("should infer correct parameter types from inputSchema", () => {
       const weatherTool = {
-        type: "function" as const,
+        type: ToolType.Function,
         function: {
           name: "get_weather",
           inputSchema: z.object({