{"service":"Santa Mailbox API","status":"running","system_locked":false,"api_key_configured":true,"api_key_length":43,"jwt_auth_configured":true,"nextauth_secret_length":44,"endpoints":{"authenticated":["/submit (requires JWT or API key)","/submissions (requires JWT, returns user's submissions only)","/send-emails (requires API key, for Cloud Scheduler)"]},"authentication":{"/submit":"JWT token (Bearer) OR X-API-Key header - Anonymous users NOT allowed","/submissions":"Authorization: Bearer <JWT token> (filters by user email)","/send-emails":"X-API-Key header (for Cloud Scheduler)"},"note":"All endpoints require authentication. Users must sign in with Google OAuth to submit letters."}