Models, Effort, and Permissions
Copilot keeps a separate model list for each experience. A model can be available in Copilot without appearing in every picker: you choose where it is enabled, then choose the default for new chats.
Where models come from
| Model source | Where you can use it |
|---|---|
| Copilot-hosted models from your license | Quick Chat and opencode |
| Your API key or endpoint (BYOK) | Quick Chat and opencode, when opencode supports that provider |
| Models reported by opencode | opencode only |
| Models reported by Claude Code | Claude only |
| Models reported by Codex | Codex only |
The available lineups can change, so the lists in Copilot are the source of truth. See Model Sources and BYOK to activate a Copilot license, add a BYOK provider, or connect an agent account.
Enable models and choose defaults
Open Settings → Copilot → Basic → Agents.
- Set Default backend to the agent you want when a new Agent Chat opens.
- Select opencode, Claude, Codex, or Quick Chat.
- Turn on the models you want shown in that experience’s model picker.
- Choose Default model. For an agent, Agent default leaves the choice to that agent.
- If the selected agent model supports it, choose Default effort. The available effort levels come from the agent and model, so they vary.
The four lists are independent:
- opencode can combine Copilot-hosted models, compatible BYOK models, and models reported by opencode.
- Claude and Codex show only models reported by their installed tools. Their CLI accounts own access and billing; BYOK models are not added to these lists.
- Quick Chat models contains Copilot-hosted and BYOK chat models. Agent-owned models do not appear here.
New BYOK chat models start enabled for both Quick Chat and opencode. You can turn either copy off without affecting the other. Models newly reported by an agent may also appear switched off until you enable them.
Choose a model while chatting
In Agent Chat, the model picker is grouped by agent. Before the first message in an empty session, choosing a model from another installed agent switches that session to the other agent. After the conversation has started, the picker stays with the current agent.
A model or effort picked beside the message box applies to that chat; it does not replace the saved Default model or Default effort. Saved agent defaults are used for new chats and multi-agent answers. Changes to an explicit default apply to open chats on their next turn; choosing Agent default leaves open chats unchanged.
In Quick Chat, the picker shows only enabled Quick Chat models. Its Default model is the model new Quick Chat conversations start with.
Model, effort, and permissions
| Experience | Choices available now |
|---|---|
| opencode | Model; effort when the model reports it; Default or Auto permissions. Plan is not available. |
| Claude | Model; effort when supported; Default, Plan, and Auto permissions. Auto mode permissions controls what Auto may approve. Show extended thinking controls whether reasoning blocks are displayed; it is separate from effort. |
| Codex | Model; effort when reported; whichever of Default, Plan, and Auto the installed adapter supports. |
| Quick Chat | Model only. Agent effort and permission controls do not apply. |
Default uses the agent’s normal approval behavior, Plan prepares a plan before editing, and Auto uses the selected agent’s automatic permission behavior.
Copilot V4 does not expose temperature, top-p, or similar tuning in these model lists. In Quick Chat, Chat Settings controls the session system prompt; it does not add Agent Chat effort or permission controls.