Copilot List error

I’m seeing a persistent issue when integrating SharePoint lists with Copilot Studio agents. Any SharePoint list I add to an agent results in an error being shown in the Copilot Studio UI, but no error message, diagnostic detail, or failure reason is surfaced.

I’ve removed and re-added the list connections multiple times and reproduced the issue across multiple agents, with the same outcome each time. Has anyone encountered this behaviour, or are there known issues or prerequisites (e.g. permissions, connector state, tenant configuration, or recent service changes) that could cause silent failures when integrating SharePoint lists?