Security

Yak is designed with security as a priority. The widget runs in an isolated iframe, all communication is origin-validated, and your tool calls execute in your own server context with your existing authentication.

Key Security Features

• Origin isolation — The widget iframe is sandboxed from your application's DOM
• Origin validation — All messages are validated against expected origins; unexpected origins are rejected
• Tool allowlisting — Only explicitly allowed tools can be executed
• Server-side execution — Tool calls run on your server with your auth and access controls
• Redirect protection — Built-in protection against open redirect attacks

Tool Security

Restricting Exposed Procedures

When using the tRPC adapter, control which procedures are available:

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

const toolAdapter = createTRPCToolAdapter({
  router: appRouter,
  createContext,
  allowedProcedures: [
    "orders.list",
    "orders.getById",
    "products.search",
  ],
});

Authentication

Tool calls receive the original Request object, so your existing auth works automatically:

const toolAdapter = createTRPCToolAdapter({
  router: appRouter,
  createContext: async ({ req }) => {
    const session = await getSession(req);
    if (!session) throw new Error("Unauthorized");
    return { user: session.user };
  },
  allowedProcedures: ["..."],
});

Input Validation

Tool inputs are validated against the JSON Schema derived from your Zod schemas. Always validate on the server side as well:

export const ordersRouter = router({
  list: protectedProcedure
    .input(z.object({
      limit: z.number().min(1).max(100).default(10),
      status: z.enum(["pending", "shipped", "delivered"]).optional(),
    }))
    .query(async ({ ctx, input }) => {
      return db.orders.findMany({
        where: { userId: ctx.userId, status: input.status },
        take: input.limit,
      });
    }),
});

Redirect Protection

The SDK validates all redirect paths:

• Allowed: Relative paths (/dashboard, /settings), hash paths (#section), query paths (?tab=profile)
• Blocked: External domain URLs, protocol-relative URLs (//evil.com)

To customize redirect behavior:

<YakProvider
  appId="your-app"
  onRedirect={(path) => {
    if (isAllowedPath(path)) {
      router.push(path);
    }
  }}
/>

Content Security Policy

If your application uses CSP headers, allow the widget iframe:

frame-src https://chat.yak.io;

Production Checklist

Before deploying to production, verify:

• Tool allowlist — Only necessary procedures are exposed
• Authentication — Tool requests require valid auth
• Rate limiting — Consider rate limiting your tool endpoint
• HTTPS — All endpoints use HTTPS
• CSP headers — Allow frame-src chat.yak.io if using CSP
• Logging — Tool invocations are logged for audit
• Allowed origins — Restrict which domains can embed the widget (configure in your dashboard)

Reporting Security Issues

If you discover a security vulnerability, please report it responsibly:

1. Do not create a public GitHub issue
2. Email security@yak.io with details
3. Include steps to reproduce if possible