claude-sonnet-4, gpt-5.5, gemini-2.5-pro).
For Codex, Claude Code, and OpenCode, append a recognized reasoning effort with a
colon, such as gpt-5.6-sol:xhigh. Other colon suffixes remain part of
the model identifier. Use a double colon to keep a recognized suffix literal, such
as provider/model::high for model provider/model:high. The
separate Reasoning effort field overrides the shorthand.
Leave empty to use the agent's default model.