{
  "service": "mail-worker",
  "model": "A (sender, recipient) pair is the unique unit for a stored code.",
  "endpoints": {
    "health": "GET /health",
    "get_otp_pair": "GET /api/otp?to=<recipient>&email=<sender>",
    "get_otp_legacy": "GET /api/otp?domain=<sender-domain>&email=<sender>",
    "list_otps": "GET /api/otps",
    "recipients": "GET /api/recipients"
  }
}