4chan vs Discord

4chan's API serves the same read-only board and thread data every page renders — board lists, catalogs, threads, and posts — as plain JSON from the dedicated a.4cdn.org host, with no registration, key, or authentication of any kind required. Media referenced by posts is served from the sibling i.4cdn.org host, and the project's own GitHub repository (4chan/4chan-API) hosts the reference client and doubles as the canonical documentation, including the rule to cap requests at one per second. Cross-origin use from a browser is limited in practice: both the docs and a live probe confirm the API's CORS policy only allows requests originating from 4chan's own board pages, so a third-party site must proxy requests server-side rather than call it directly from client-side JavaScript.

Discord's REST and Gateway APIs let bots and apps manage servers, channels, messages, and slash commands, authenticated with a bot token for server-side integrations or OAuth2 for user-facing flows like account linking. Rate limits are enforced per route and per bucket, and most guild-management scopes only work once the bot has been added to a server with matching OAuth2 permission scopes.