# NousResearch/hermes-agent · Plugin hook SystemExit isolation fix

## Open now

- Nothing open on GitHub.

These items address a bug where SystemExit raised inside plugin hook callbacks could escape isolation and terminate the process. The work focuses on catching and containing BaseException/SystemExit from hook callbacks.

## 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 #117563. Verify it addresses your case.
- **Recommended:** read PR #117563 (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-117563`. 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evidence (`STRUCTURAL_SPANNING`): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.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

- #117303: Plugin hook isolation does not hold for BaseException (SystemExit escapes on caller-thread hooks)

## Prior & competing PRs

- **#117563: fix(plugins): a plugin callback's sys.exit() no longer kills the turn (#117303, salvage #117315)**. merged to main · fix tier `verified`
  - maintainer direction: category `merged`
  - files: `hermes_cli/plugins_dispatch.py`, `tests/hermes_cli/test_plugins.py`
- **#117315: fix(plugins): isolate SystemExit from hook callbacks**. closed without merge
  - maintainer direction: category `merged_via`; implication `superseded`; refs `656c1c9bda`, `#117563`

## Fix status

- Merged to main in PR #117563 (cited above). No release data is tracked. Verify downstream.
- Fix last verified (merged) `2026-09-20`.