HTTP Archive : The HTTP Archive tracks how the Web is built.
HTTPie : HTTPie—aitch-tee-tee-pie—is a command line HTTP client with an intuitive UI, JSON support, syntax highlighting, wget-like downloads, plugins, and more
Vcr : Record your test suite's HTTP interactions and replay them during future test runs for fast, deterministic, accurate tests.
endpoints.dev : Use your unique endpoint wherever you need. We'll store the details of any HTTP request and display them below.
Webhook Tester : Webhook Tester allows you to easily test webhooks and other types of HTTP requests.