Running multiple agents on the same project and hitting this problem: one agent changes a response shape on the backend, the frontend agent consuming that endpoint has no idea anything moved. It keeps coding against the old contract. The build passes, the types check out locally, and the breakage only shows up when you actually run the thing end to end.

The context lives in two separate chat sessions. Neither agent knows what the other touched. By the time you notice, you're debugging a silent failure and trying to reconstruct which session changed what and when.

Curious how others handle this. Do you keep a shared contract file that both agents read before starting work? Pin the schema somewhere both can see it? Or just accept the breakage and fix it manually when it surfaces?