What you are experiencing is very likely a recent platform behavior change rather than an issue in your configuration.
The SharePoint “Agent Link” web part does not fully control how the agent is rendered. Instead, it relies on the current Copilot Studio / SharePoint integration behavior, which has been evolving. Recently, Microsoft has been shifting towards opening agents using a dedicated “.agent” experience (similar to file preview tabs), and this can override the previous side-pane embedded behavior.
Why this is happening:
- The agent is now being treated as a resource that opens in its own experience (new tab / preview surface)
- SharePoint is delegating the launch to that experience instead of rendering it in the side pane
- This change can happen without tenant-side configuration changes because it is controlled by the platform rollout
This explains why:
- It worked before
- It changed suddenly
- It is consistent across browsers, pages, and re-deployments
Important limitation:
At the moment, there is no supported setting to force the agent back into the old embedded side panel experience when using the out-of-the-box “Agent Link” web part. The rendering mode is not configurable.
Workarounds you can consider:
1) Use an alternative embedding approach
Instead of relying on the Agent Link web part, embed the agent using:
- A custom web part
- An iframe (if supported in your tenant)
- Or a custom front-end using Direct Line / Web Chat
2) Provide a controlled launch experience
If full embedding is not possible, you can:
- Present the agent as a clearly labeled “Open assistant” action
- Open it in the new experience intentionally (rather than relying on inline rendering)
3) Monitor platform updates
Since this appears to be a platform-driven change, the behavior may evolve again. It’s worth tracking Copilot Studio / SharePoint integration updates, as Microsoft may reintroduce or standardize embedded experiences.
