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

# reasoning_not_supported

> HTTP 400 — Model does not support reasoning/extended thinking.

## HTTP status

`400 invalid_request_error`

## Typical cause

The request enables reasoning or extended thinking (`thinking: { type: "enabled" }`) but the selected model does not support it.

## Resolution

Remove the thinking/reasoning parameter or choose a model that supports extended thinking.