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NousResearch/hermes-agent

Windows MCP stdio process tree cleanup

Cluster 108084 · mcp. Data as of

1 open item. Fix merged in #123003 on 27 Sep 2026. Check it covers your case.

The short answer

1open issue
0open PRs
3items grouped
Known?
Yes. 3 related items grouped here, 0 issues already closed.
Fix event
A fix was merged to main in PR #123003. Check it covers your case. No release data is tracked.
Tracker
The maintainers' tracker marks this unresolved. That is separate from the fix event.
Still open
1 issue and 0 PRs.

These items address a Windows-specific issue where MCP stdio child processes and their descendants (e.g., cmd.exe/npx chains) are not fully terminated on disconnect or reconnect, because the POSIX-style process group reaper does not reach them. Proposed approaches involve Job Objects and explicit tree reaping.

Open issues1

  • Issue#108084Windows: MCP reconnect leaks stdio grandchildren — POSIX killpg reaper can't reach the cmd.exe/npx chain

Open PRs0

No open pull requests.

Fixes on record

Merged to main. A stamp counts the issues a fix is linked to.

  • #123003 fix(mcp): kill Windows stdio MCP orphan trees (Job Object + tree reaping)

    merged to main

    files: hermes_cli/process_identity.py, tests/tools/test_mcp_windows_orphan_fix.py, tools/mcp_tool_lifecycle.py, tools/mcp_tool_transport.py

1 PR closed without merging

From the close comments: superseded by another PR 1

  • #108093 fix(tools): reap Windows MCP stdio process trees · superseded by another PR → 0cd93f0, #108084, #131331, #123003
How this cluster was grouped
  • Link evidence (structural links throughout): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.
  • Pairwise link density 0.67: the share of item 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.

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At a glance

Subsystem
mcp
Merged PRs
#123003
Closed issues
0
Attempts
1 PR closed without merging
Fix link checked
27 Sep 2026

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