How to Use an External AI Model in Copilot Studio

Microsoft Copilot Studio can use supported models from Anthropic, Mistral, and xAI as an agent's primary model. A maker selects the model in the agent editor, but two administrator controls must already allow it: external models must be enabled for the Power Platform environment, and the individual provider must be allowed in the Microsoft 365 admin center.

External and preview models are separate classifications. An external model may also be marked preview or experimental, but allowing one category does not automatically allow the other.

Before selecting an external model

• Confirm that the agent's Power Platform environment permits external models.
• Confirm that the required provider is enabled for the intended users or security groups in Microsoft 365.
• Review the provider's terms, data-processing location, privacy implications, and organizational compliance requirements.
• Check the model's status. Microsoft advises against using preview or experimental models in production.
• Create a representative evaluation set so the new model can be compared with the current one.

Available providers and models can change. Use Microsoft's external-model documentation as the current source of truth.

Select the model in Copilot Studio

Current agent experience

1. Open the agent in Copilot Studio.
2. Select the Build tab.
3. In the components panel, open the Model list.
4. Choose the supported model from Anthropic, Mistral, or xAI.
5. Select Save.

Classic authoring experience

1. Open the agent's Overview page.
2. Find the Model section.
3. Select a model listed under Anthropic, Mistral, or xAI.

The interface shown depends on the environment and agent experience. Selecting a model changes the primary model used by the agent; it does not eliminate the need to test topics, tools, knowledge sources, and safety behavior.

If an external model is visible but unavailable

A visible but disabled choice usually means access was removed or not granted to your user or environment. Ask an administrator to check both control layers:

1. Power Platform admin center: enable the external-model rule for the environment or managed environment group.
2. Microsoft 365 admin center: allow the specific AI provider and assign access to the required users or Microsoft Entra ID security groups.

Provider changes can take time to propagate. Do not repeatedly change unrelated settings while access is updating.

If the model does not appear

• Verify that the selected provider is allowed in Microsoft 365, not merely that external models are enabled in Power Platform.
• Check whether the model is offered in the agent experience, environment, and region you are using.
• Confirm that preview and experimental models are permitted if the desired model has that label.
• For experimental models, the environment may also need the setting that allows data movement across regions.
• Refresh Copilot Studio after the administrator changes have propagated.

What happens if access is later removed?

According to Microsoft, an agent using a blocked external model attempts to move to a suitable internal model. If no suitable internal model is available, the agent reports an error and its maker must select an internal model. Treat this fallback as a recovery behavior, not a tested migration plan: response quality, latency, tool use, and message consumption may change.

External models and preview models are different controls

Test before publishing

1. Run the same representative prompts against the old and new models.
2. Compare factual accuracy, instruction following, tone, citations, structured output, and refusal behavior.
3. Test every action, connector, knowledge source, and handoff path used by the agent.
4. Measure latency and message or credit consumption under realistic load.
5. Review data residency, retention, provider terms, and support expectations with the appropriate owners.
6. Document a rollback model and verify that it remains selectable.

Do not publish an agent with a preview or experimental model as though it were production-ready. Microsoft warns that these models can vary in quality, latency, availability, and message consumption, and they may time out or be retired. The primary model selection guide contains the current limitations.