Previous commit put tool_choice at the top level of params. Open WebUI
drops that silently — apply_model_params_to_body has a whitelist of
mapped param names (temperature, top_p, etc.) and tool_choice isn't
on it. The Custom Parameters UI section also only iterates
params.custom_params, which is why the value didn't appear there
after importing the preset.
Correct location is the custom_params sub-dict, where values go
through json.loads before being merged into the outgoing chat
completion body. 'required' stays a string after the failed
json.loads and ends up exactly where the OpenAI / Ollama tools spec
expects it.
Source: src/lib/components/chat/Settings/Advanced/AdvancedParams.svelte
(UI binding) and backend/open_webui/utils/payload.py (serialization).
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
57_WolveandClaude Opus 4.7
780ce42711