unsupported_api_version - Agnes


HTTP status	`400 Bad Request` or `410 Gone`
Code	`unsupported_api_version`
Retry?	No — upgrade your client or pin a newer version.

When this happens

You set the Agnes-Version header to a date that is older than the server’s current minimum supported version. The server cannot reliably honour the old contract and refuses the request rather than guess.

Example response

{
  "detail": "Agnes-Version 2024-11-01 is no longer supported. Minimum supported version: 2026-01-01.",
  "code": "unsupported_api_version",
  "request_id": "5b3f6c7e-7d24-4d40-9b12-3a59c01c6e91",
  "doc_url": "https://docs.lasscyber.com/errors/unsupported_api_version"
}

How to fix

If you pinned the version yourself: bump the Agnes-Version value to a more recent date. The current date version is in the OpenAPI document (sdk/openapi/openapi.json) and is 2026-04-16 at the time of writing.
If your SDK is pinning it: upgrade to the latest minor of the SDK. See Versioning.
If you have not pinned it: this should never happen — the API defaults to the latest version when no header is sent. If you see this without a pin, file a ticket with the request_id.

Deprecation timeline

The minimum supported version moves forward roughly once a year. Deprecation notices ship in the SDK CHANGELOG and the API release notes; you have at least six months of warning before a date version is removed.

SDK behaviour

SDK	Exception
Python	`agnes.ValidationError` (with `code == "unsupported_api_version"`)
TypeScript	`ValidationError` (with `code === "unsupported_api_version"`)

SDKs do not retry — the only recovery is to bump the version.