There's a large dropoff of participant prompts submitted: https://mixpanel.com/project/3851272/view/4346958/app/boards#id=10909324&editor-card-id=%22report-87907081%22 
This is likely a result of new VSCode changes around how participants work. Using the "@MongoDB" participant out of the box gives a `Copilot model not found` error now. This ticket involves looking at what the changes are and how we can get the participant fixed to be easily used again.
On a quick glance it looks like it might be a new change to required permission with `selectChatModels`: https://code.visualstudio.com/api/extension-guides/ai/language-model#send-the-language-model-request 

Not sure what the best approach is here to this. We should see if it's something we can easily fix, or if it's something we need to add a check for user consent for in order to use the model. If it's not easily done we may want to consider removing the participant altogether. Let's open a discussion in #vscode-extension about that if that's the case.

https://code.visualstudio.com/api/extension-guides/ai/language-model