Errors

A failed call returns the same witness envelope with ok: false and a populated error; the engine is fail-closed and never fabricates a value to recover.

{
  "ok": false,
  "tool": "find_twins",
  "generation": null,
  "result": null,
  "error": {
    "code": "invalid_arguments",
    "message": "unknown argument(s) ['k']"
  }
}

HTTP status codes

• 400 — validation
• 401 — missing/invalid key or token
• 403 — quota exceeded or tier-gated
• 404 — entity not found
• 429 — rate-limited (retry after Retry-After)
• 5xx — our problem; we'll find it before you do