# NousResearch/hermes-agent · Fix recursive error traversal in MCP connection errors

## Open now

- Nothing open on GitHub.

These items address a RecursionError caused by unbounded traversal of cyclic exception chains when a stdio MCP server binary is missing. The fix bounds the nested connection error walk so the real underlying error is reported instead.

## 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 #112200. Verify it addresses your case.
- **Recommended:** read PR #112200 (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-112200`. 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evidence (`STRUCTURAL_SPANNING`): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.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

- #111952: hermes mcp test: RecursionError (unbounded exception-chain walk) when a stdio server's binary is missing

## Prior & competing PRs

- **#112200: fix(mcp): hermes mcp test reports the real connect error instead of RecursionError on cyclic exception chains (#111952, #111997, salvage #111961)**. merged to main · fix tier `verified`
  - maintainer direction: category `merged`
  - files: `contributors/emails/205820855+MrMongstad@users.noreply.github.com`, `tests/tools/test_mcp_tool_errors.py`, `tests/tools/test_mcp_tool_session_expired.py`, `tools/mcp_tool_errors.py`
- **#111961: fix(mcp): bound nested connection error traversal**. closed without merge
  - maintainer direction: category `merged_via`; implication `superseded`; refs `4b1215be2f`, `#112200`

## Fix status

- Merged to main in PR #112200 (cited above). No release data is tracked. Verify downstream.
- Fix last verified (merged) `2026-09-16`.