Custom Tools and Toolkits (Experimental)

// ── Standalone tool ─────────────────────────────────────────────
// Internal data lookup — no Composio auth needed.
// ctx.userId identifies which user's session is running.
const profiles: Record<string, { name: string; email: string; tier: string }> = {
  "user_1": { name: "Alice Johnson", email: "alice@myapp.com", tier: "enterprise" },
  "user_2": { name: "Bob Smith", email: "bob@myapp.com", tier: "free" },
};

const getUserProfile = experimental_createTool("GET_USER_PROFILE", {
  name: "Get user profile",
  description: "Retrieve the current user's profile from the internal directory",
  inputParams: z.object({}),
  execute: async (_input, ctx) => {
    const profile = profiles[ctx.userId];
    if (!profile) throw new Error(`No profile found for user "${ctx.userId}"`);
    return profile;
  },
});

// ── Extension tool ──────────────────────────────────────────────
// Wraps Gmail API with business logic. Inherits auth via extendsToolkit,
// so ctx.proxyExecute() handles credentials automatically.
const sendPromoEmail = experimental_createTool("SEND_PROMO_EMAIL", {
  name: "Send promo email",
  description: "Send the standard promotional email to a recipient",
  extendsToolkit: "gmail",
  inputParams: z.object({
    to: z.string().describe("Recipient email address"),
  }),
  execute: async (input, ctx) => {
    const subject = "You're invited to try MyApp Pro";
    const body = "Hi there,\n\nWe'd love for you to try MyApp Pro — free for 14 days.\n\nBest,\nThe MyApp Team";
    const raw = btoa(`To: ${input.to}\r\nSubject: ${subject}\r\nContent-Type: text/plain; charset=UTF-8\r\n\r\n${body}`);

    const res = await ctx.proxyExecute({
      toolkit: "gmail",
      endpoint: "https://gmail.googleapis.com/gmail/v1/users/me/messages/send",
      method: "POST",
      body: { raw },
    });
    return { status: res.status, to: input.to };
  },
});

// ── Custom toolkit ──────────────────────────────────────────────
// Groups standalone tools that don't need Composio auth under a toolkit.
// Tools inside a toolkit cannot use extendsToolkit.
const userManagement = experimental_createToolkit("USER_MANAGEMENT", {
  name: "User management",
  description: "Manage user roles and permissions",
  tools: [
    experimental_createTool("ASSIGN_ROLE", {
      name: "Assign role",
      description: "Assign a role to a user in the internal system",
      inputParams: z.object({
        user_id: z.string().describe("Target user ID"),
        role: z.enum(["admin", "editor", "viewer"]).describe("Role to assign"),
      }),
      execute: async ({ user_id, role }) => ({ user_id, role, assigned: true }),
    }),
  ],
});

// ── Bind to session ─────────────────────────────────────────────
// Pass custom tools and toolkits via the experimental option.
// session.tools() returns both remote Composio tools and your custom tools.
const composio = new Composio({ apiKey: "your_api_key" });

const session = await composio.create("user_1", {
  toolkits: ["gmail"],
  experimental: {
    customTools: [getUserProfile, sendPromoEmail],
    customToolkits: [userManagement],
  },
});

const tools = await session.tools();