The Request object

request.headers, request.cookies, request.url, request.query_params — everything the client sent.

Code example

@router.get('/x')
async def handler(request: Request):
    user_agent = request.headers.get('user-agent')
    token = request.cookies.get('access_token')
    next_url = request.query_params.get('next', '/')

How it works

The Request object is FastAPI's representation of the incoming HTTP request. It exposes headers, cookies, query params, the URL, the client's IP, and the body (for POST/PUT). Most routes need it for cookie-based auth (reading the access_token cookie) or for building absolute URLs. You ask for it by adding `request: Request` to the function signature — FastAPI sees the type annotation and injects it.