Get an API key

Email verification + key issuance. Phase 1 free tier (1K req/day).

Signup flow integration is 5/3-5/9 sprint scope (cross-lane work with takumi-2 backend). Until then, use the public sandbox with demo key:

Try sandbox →

Backend: POST /api/v1/developers/signup (PR #269 takumi-2 backend, 24h email verify TTL, RFC 6749 §4.4 OAuth flow). Phase 1.5 polish: this page wires UI to that endpoint.