After context compression (manual /compress or auto), run_agent's
_compress_context ends the current session and creates a new continuation
child session, mutating agent.session_id. The classic CLI held its own
self.session_id that never resynced, so /status showed the ended parent,
the exit-summary --resume hint pointed at a closed row, and any later
end_session() call (from /resume <other> or /branch) targeted the wrong
row AND overwrote the parent's 'compression' end_reason.
This only affected the classic prompt_toolkit CLI. The gateway path was
already fixed in PR #1160 (March 2026); --tui and ACP use different
session plumbing and were unaffected.
Changes:
- cli.py::_manual_compress — sync self.session_id from self.agent.session_id
after _compress_context, clear _pending_title
- cli.py chat loop — same sync post-run_conversation for auto-compression
- cli.py hermes -q single-query mode — same sync so stderr session_id
output points at the continuation
- hermes_state.py::end_session — guard UPDATE with 'ended_at IS NULL' so
the first end_reason wins; reopen_session() remains the explicit
escape hatch for re-ending a closed row
Tests:
- 3 new in tests/cli/test_manual_compress.py (split sync, no-op guard,
pending_title behavior)
- 2 new in tests/test_hermes_state.py (preserve compression end_reason
on double-end; reopen-then-re-end still works)
Closes#12483. Credits @steve5636 for the same-day bug report and
@dieutx for PR #3529 which proposed the CLI sync approach.
