The schema server's backstop ended every session with "session refused
a packet", including when the fault was the server's own: for example a
handler's response too large to send, or a refusal the handler did not
type. Decoding and handling are now two catches:
- A message that cannot be decoded is the peer's. The session ends with
the refusal reason.
- A handler fault ends the session with "server could not handle a
message".
The transport's EndRefusedPeer becomes EndPeerSession(peer, reason). It
reports whether it ended the session, so the log says when a response
that failed after its first fragment had already ended it over the send.
Before, the log reported that it ended a session that was already gone.
The comment said that ending the session matched cultmesh-py. It does
not: Python silently skips a malformed frame. The honest anchor is the
C# TCP schema server, whose ServePeerAsync ends the one peer whose
message fails to decode or handle. The comment now says so.
Pinned, each by a test that kills its mutant:
- a handler fault's goodbye carries the server's reason, not the refusal
(mutant: the refusal reason);
- the post-fragment-0 path logs that the session had already ended
(mutant: a constant outcome);
- EndPeerSession says no goodbye to a replaced peer's endpoint (mutant:
the Ended check dropped);
- a refused peer's frames still queued are never handled (mutant: the
queue purge dropped).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>