Service Principal authentication works with Lakehouse Data Agent but fails with Semantic Model

Hi Antoine1733 ,

Thanks for reaching out to the Microsoft fabric community forum.

Thanks for sharing your scenario. What you are seeing is expected behavior. At the moment, Service Principal authentication is not supported when a Data Agent connects to a Semantic Model. Even though the authentication with ClientSecretCredential succeeds, the queries fail because accessing a Semantic Model requires a user identity context. That is why general prompts like greetings work, but any request that needs data from the Semantic Model returns an error.

In contrast, Lakehouse agents work with Service Principals because you can assign permissions directly to the Service Principal for the Lakehouse. This allows the agent to read data without needing a signed‑in user. For Semantic Models, the recommended approach right now is to use user‑based authentication such as InteractiveBrowserCredential.

There is currently no official timeline for Service Principal support with Semantic Model Data Agents. The best way to stay updated is to keep an eye on Fabric documentation and release notes for future changes. I hope this helps clarify the behavior you are seeing.

Best Regards, 
Community Support Team