HTTP status
400 invalid_request_error
Typical cause
The request setstool_choice: "required" but the selected model doesn’t reliably guarantee a tool call in the response. Auriko rejects this combination to prevent silent failures in agentic pipelines.
Resolution
Usetool_choice: "auto" instead. Models still call tools when prompted appropriately. Alternatively, remove any provider constraint to allow routing to a capable provider.