HTTP Headers

HTTP Headers are key/value metadata sent along with HTTP requests and responses. In Brevvie Python + AI — Section 4: APIs, Postman & Calling the Web, they are part of the core request/response anatomy learners are expected to recognize.

Request-side examples

• Accept tells the server what response format the client wants
• User-Agent identifies the calling client
• some APIs use headers for auth instead of query params

Response-side examples

• Content-Type describes the returned body format
• APIs may also return rate-limit or caching information in headers

Why it matters

When a request fails or behaves strangely, headers are one of the first places to inspect.