Models, effort and fast mode
Choose the model and how hard it thinks, per session, and change them while you work.
Every session has its own model and effort level. You set them when you start the session and can change them at any time.
The run settings pill
The composer's toolbar has one pill that shows the current choice, for example Opus 5.5 · high. Click or tap it to open the run settings. With a mouse it opens as a small panel; on a phone it slides up from the bottom.
There you'll find:
- The model list, with a Search models… field. Star the models you use most to keep them at the top.
- Default, which leaves the choice to the agent.
- Effort, for agents that have it.
- Fast mode, on models that support it.
- Account and Mode: see Accounts and Access levels.
Typing /model in the composer opens the same list.
Where the models come from
supermux asks each agent which models your sign-in can use, and refreshes the list every 15 minutes. So the list matches your plan: a new model shows up without updating supermux.
OpenCode's list depends on the providers you've connected to it.
Effort
Effort is how much the model thinks before it answers. More effort is slower and uses more of your limits.
| Agent | Levels |
|---|---|
| Claude Code | low, medium, high, xhigh, max |
| Codex | What each model supports |
| Grok | What each model supports, on models that have it |
| Cursor, OpenCode, Antigravity | Pick a model instead. Antigravity puts the level in the model's name. |
A new session uses the level you picked last time for that agent. If you've never picked one, it starts on high where that exists.
Fast mode
Fast mode asks for faster answers on models that offer it:
- Claude Code: on Opus 4.8 and newer Opus models.
- Codex: on models with OpenAI's priority tier.
Turn it on with Fast mode in the run settings of a running session. A bolt appears on the pill while it's on.
Changing settings while the agent works
You can change the model, effort and fast mode in the middle of a session. Claude Code, Codex, Grok and Antigravity pick up the change when the current turn ends, so nothing is cut off. Cursor and OpenCode switch right away.
If a change can't be applied, the old settings come back and the chat says why.