@yak-io/trpc

Adapters that turn tRPC procedures into Yak tool definitions. This package plugs directly into @yak-io/javascript and works seamlessly with the Next.js helpers.

What you get

• createTRPCToolExecutor – a thin wrapper that turns procedure names into a tool executor function.
• createTRPCToolAdapter – a higher level helper that returns a full ToolSource (manifest + executor) that can be passed straight into createYakHandler or createNextYakHandler.
• buildToolManifest – introspection utility used by the adapter (exposed for custom pipelines).

Installation

pnpm add @yak-io/trpc @yak-io/javascript

You also need @trpc/server (v10+ or v11+) in your project.

Usage

1. Build a tRPC adapter

By default, all procedures from your router are exposed as tools:

import { createTRPCToolAdapter } from "@yak-io/trpc";
import { appRouter, createContext } from "@/server/trpc";

// All procedures are available
const trpcTools = createTRPCToolAdapter({
  router: appRouter,
  createContext: async ({ req }) => createContext({ req }),
});

Restricting procedures

Use allowedProcedures to whitelist specific procedures:

const trpcTools = createTRPCToolAdapter({
  router: appRouter,
  createContext: async ({ req }) => createContext({ req }),
  allowedProcedures: ["orders.list", "orders.detail"],
});

Use disallowedProcedures to block specific procedures while allowing the rest:

const trpcTools = createTRPCToolAdapter({
  router: appRouter,
  createContext: async ({ req }) => createContext({ req }),
  disallowedProcedures: ["admin.deleteUser", "billing.refund"],
});

2. Attach it to a Yak handler

import { createYakHandler } from "@yak-io/javascript/server";

export const { GET, POST } = createYakHandler({
  routes: () => Promise.resolve([{ path: "/" }]),
  tools: trpcTools,
});

If you are in a Next.js app, simply pass the adapter to createNextYakHandler instead.

3. Executor only

If you already generate manifests elsewhere you can still use the lower level executor helper:

import { createTRPCToolExecutor } from "@yak-io/trpc";

const executeTool = createTRPCToolExecutor({
  router: appRouter,
  createContext,
  allowedProcedures: ["orders.list"],
});

Then supply getTools + executeTool to any Yak handler.

Types

All tool/route/chat config types are re-exported from @yak-io/javascript/server, e.g.

import type { ToolDefinition, ToolManifest, ToolExecutor } from "@yak-io/trpc";

Security tips

• For production apps, consider using allowedProcedures to restrict to the minimal surface area needed by the assistant, or use disallowedProcedures to block sensitive operations.
• Build per-request contexts so each call is authorized with the user session from req.
• Combine the adapter with additional ToolSources (e.g., GraphQL or REST) by passing arrays to createYakHandler / createNextYakHandler.

License

Proprietary - see LICENSE file