Cross-repo requests

The failure this prevents

A frontend agent needs an endpoint that does not exist yet. Left alone it stubs the response, invents a payload shape, and writes code against a contract the backend never agreed to. The stub survives into review and the shapes do not match. The same happens in reverse when a backend agent guesses at how a client consumes a field.

If another repo owns the change, ask the session that owns that repo. Do not guess the contract, and do not stub it silently.

Finding the peer

ListAgents lists the Claude sessions running on this machine. Each row leads with the name that addresses it. If the repo you need has no session listed, stop and tell the user to open one there, then continue. Do not start implementing against an assumed contract while you wait.