`app.get()`

Registers a route handling HTTP GET requests for a URL pattern.

Since Fastify 5 Spec ↗

Syntax

app.get(url, options?, handler)

Parameters

Name	Type	Required	Description
`url`	`string`	No	The route path, supporting :params and wildcards.
`options`	`RouteShorthandOptions`	No	Optional schema, hooks, and config.
`handler`	`Function`	No	Async handler receiving (request, reply).

Returns

FastifyInstance — The instance, for chaining.

Examples

import Fastify from 'fastify';

const app = Fastify();

app.get<{ Params: { id: string } }>('/cats/:id', async (req) => {
  return { id: req.params.id };
});

app.get(
  '/health',
  { schema: { response: { 200: { type: 'object', properties: { ok: { type: 'boolean' } } } } } },
  async () => ({ ok: true }),
);

Notes

Returning a value resolves the response automatically; you rarely need reply.send(). Add a `schema` for request validation and faster response serialization. Use TypeScript route generics for typed params and body.