@mastra/fastify

@mastra/fastify

Fastify server adapter for Mastra, enabling you to run Mastra with the Fastify framework.

Installation

npm install @mastra/fastify fastify

Usage

import Fastify from 'fastify';
import { MastraServer } from '@mastra/fastify';
import { mastra } from './mastra';

const app = Fastify({ logger: true });
const server = new MastraServer({ app, mastra });

await server.init();

app.listen({ port: 3000 }, (err, address) => {
  if (err) {
    console.error(err);
    process.exit(1);
  }
  console.log(`Server running on ${address}`);
});

Adding Custom Routes

Add routes directly to the Fastify app with access to Mastra context:

// Routes added after init() have access to Mastra context
app.get('/health', async request => {
  const mastraInstance = request.mastra;
  const agents = Object.keys(mastraInstance.listAgents());
  return { status: 'ok', agents };
});

Configuration Options

const server = new MastraServer({
  app,
  mastra,
  prefix: '/api/v2', // Route prefix
  openapiPath: '/openapi.json', // OpenAPI spec endpoint
  bodyLimitOptions: {
    maxSize: 10 * 1024 * 1024, // 10MB
    onError: err => ({ error: 'Payload too large' }),
  },
  streamOptions: { redact: true }, // Redact sensitive data from streams
});

Context Variables

Access these in route handlers via request:

Key	Description
mastra	Mastra instance
requestContext	Request context map
abortSignal	Request cancellation signal
tools	Available tools

Multipart File Uploads

For multipart file uploads, register @fastify/multipart:

import multipart from '@fastify/multipart';

await app.register(multipart);

Related Links

• Server Adapters Documentation
• Fastify Documentation