How to read an HTTP request
The client sends a method, address and optional body. The server returns a status, headers and optional body. Diagnose API errors by inspecting both messages.
A concrete example
When an order request returns 400, compare the submitted fields with the API contract. For 401, inspect authentication.
POST /orders → 201 CreatedExplain it yourself
How does failing to reach a server differ from receiving 400?
How to study this
Write your reasoning first. Check the original documentation, identify an assumption, then try a different example. Reading this page does not count as verified skill evidence.
Source and review
Original RealDeveloper explanation; last source check: .