Fastify

easy5 minfastify-server.ts

Same API, but your service runs on Fastify.

What it shows

The code

fastify-server.ts

import { Agent, Cogitator, calculator } from '@cogitator-ai/core';
import { cogitatorPlugin } from '@cogitator-ai/fastify';
import Fastify from 'fastify';

const apiKey = process.env.GOOGLE_API_KEY;
if (!apiKey) throw new Error('Set GOOGLE_API_KEY');

const cog = new Cogitator({ llm: { providers: { google: { apiKey } } } });

const assistant = new Agent({
  name: 'assistant',
  description: 'General assistant with a calculator tool',
  model: 'google/gemini-3.5-flash-lite',
  instructions: 'You are a helpful assistant. Use tools when appropriate. Be concise.',
  tools: [calculator],
  temperature: 0.3,
});

const fastify = Fastify({ logger: false });

await fastify.register(cogitatorPlugin, {
  cogitator: cog,
  agents: { assistant },
  prefix: '/cogitator',
  enableSwagger: false,
});

await fastify.listen({ port: 3101, host: '0.0.0.0' });
console.log('Listening on http://localhost:3101/cogitator');

Run it

install · bash

pnpm add @cogitator-ai/core @cogitator-ai/fastify fastify

EnvironmentGOOGLE_API_KEY

run · bash

GOOGLE_API_KEY=your-key npx tsx fastify-server.ts

Or run the full example from a clone of the repository (keys in .env):

repository · bash

npx tsx examples/integrations/02-fastify-server.ts

Try it

Try it · bash

curl -X POST http://localhost:3101/cogitator/agents/assistant/run \
  -H 'Content-Type: application/json' -d '{"input": "What is 123 * 456?"}'

Fastify

What it shows

The code

Run it

Try it

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