Same issue. I'm using Xcode Version 26.0.1 (17A400) on macOS v26.0.1 (25A362) and I restarted Xcode, turned Apple Intelligence off and then back on, and I got the error from a Playground and a locally built app (FoundationModelsCodeAlong). I fixed the issue (for now) by restarting my Mac. Then, both the playgrounds and apps