# NousResearch/hermes-agent · Fix KeyError from concurrent PTY session reaping

## Open now

- Nothing open on GitHub.

A KeyError could occur when concurrent reap operations attempted to remove the same key from the PTY session registry. The fix makes reaping skip already-removed keys rather than raising an error.

## TL;DR

- 3 member(s): 0 open issue(s), 1 closed issue(s), 0 open PR(s), 1 merged PR(s), 1 PR(s) closed without merging.
- A fix was merged to main in PR #106511. Verify it addresses your case.
- **Recommended:** read PR #106511 (and any competing PRs below) before filing. Confirm the merged change covers your symptom.

## Maintainer resolution verdict

- Internal-tracker verdict over this cluster's issue members: `resolved` · deciding PR(s): `pr-106511`. This is distinct from the fix status above. Weigh it yourself.

## How this cluster was grouped

- Link evidence (`STRUCTURAL_SPANNING`): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.
- Pairwise link density `0.67`: the share of member pairs that carry a link, counting a structural link in full and a relevance-only link at 0.36. `1.00` means every pair is linked.

## Closed / duplicate issues

- #106400: KeyError in PtySessionRegistry.reap_idle: concurrent reap pops same key (observed with NUL byte in session key)

## Prior & competing PRs

- **#106511: fix(cli): concurrent PTY reaps no longer raise KeyError into the terminal websocket (#106400, salvage #106415)**. merged to main · fix tier `verified`
  - maintainer direction: category `merged`
  - files: `hermes_cli/pty_session.py`, `tests/test_pty_session.py`
- **#106415: fix(cli): concurrent PTY reaps skip already-popped keys instead of raising**. closed without merge
  - maintainer direction: category `merged_via`; implication `superseded`; refs `95cfcba353`, `#106511`

## Fix status

- Merged to main in PR #106511 (cited above). No release data is tracked. Verify downstream.
- Fix last verified (merged) `2026-09-09`.