`ChatModelGPT5_1Mini` is not a publicly available model

[dlo]

ChatModelGPT5_1Mini is exposed in aliases.go:

https://github.com/openai/openai-[go/blob/d3e2e4ee1d0947fad6e14d4d6c075dcb1617bd53/aliases.go#L46-L47](https://www.golinks.io/blob/d3e2e4ee1d0947fad6e14d4d6c075dcb1617bd53/aliases.go#L46-L47?trackSource=github)

However, if you try to use it, you get an error:

{
  "message": "The requested model 'gpt-5.1-mini' does not exist.",
  "type": "invalid_request_error",
  "param": "model",
  "code": "model_not_found"
}

Which is expected, because gpt-5.1-mini is not an available model per the models listed on the pricing page: