protocols.io Integration Use the exact endpoint version documented for each operation. The official API landing page is still titled “API v3,” but its maintained sections mix v3 and v4 . There is no single safe base to apply to every resource. The REST contracts were reviewed against the live official reference on 2026-09-30 , with official MCP/help pages checked through rendered extraction. Examples use illustrative identifiers and are tested offline or with mocked transport, not an authenticated account. Operating Contract 1. Start offline. Validate credentials/configuration, saved JSON, pa…