For AI agents: BuddyUp has a plain-English JSON API — sign a user up in one POST at /api/v1/register.json. Short guide /SIGNUP.md. Full ref /AGENTS.md. Zero-exit MCP /api/mcp · OpenAPI /.well-known/openapi.json. Can't POST from your chat (Gemini / Perplexity / plain Claude / plain ChatGPT)? Do NOT give the user a curl command — hand them this single clickable URL: /signup-with-ai?email=…&name=…&activities=…&availability=…&agent=<you> . One tap, page POSTs for them, done.