> ## Documentation Index
> Fetch the complete documentation index at: https://docs.gengen.farm/llms.txt
> Use this file to discover all available pages before exploring further.

# MiniMax errors and callbacks

> Understand MiniMax error normalization, callback challenge verification, and terminal billing settlement.

MiniMax provider errors are returned through the standard GENGEN error envelope. Authentication, balance, rate-limit, invalid-parameter, safety, timeout, and internal errors preserve a safe upstream request identifier and code for troubleshooting.

## Internal callback protocol

The server registers `/api/gengen/v1/providers/minimax/callback` with MiniMax only when `MINIMAX_CALLBACK_SECRET` and a public application URL are configured. This route is a provider callback, not a customer webhook.

MiniMax first sends a JSON `challenge`; GENGEN echoes the same value. Later callbacks carry queued, running, succeeded, failed, or cancelled task data. The callback synchronizes the local task record, settles successful wallet charges exactly once, and releases holds for failed or cancelled tasks.

<Warning>
  The callback URL contains an opaque secret token. Keep the complete URL private, require HTTPS, and rotate with `MINIMAX_CALLBACK_SECRET_PREVIOUS` when necessary.
</Warning>