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MCP stdio command lookup env isolation fixes

NousResearch/hermes-agent · cluster 117213

Data as of

Nothing open on GitHub. Fix merged in #117626. Check it covers your case.

The short answer

0open issues
0open PRs
5items grouped
Known?
Yes. 5 related items grouped here, 1 issue already closed.
Fix event
A fix was merged to main in PR #117626. Check it covers your case. No release data is tracked.
Tracker
The maintainers' tracker marks this resolved, deciding PR #117626. That is separate from the fix event.
Still open
Nothing open on GitHub.

Multiple fixes addressing how MCP stdio command lookup reads and mutates environment variables, specifically preventing fallback to or mutation of the parent process's PATH and PATHEXT. One unrelated member covers machine-facts platform detection.

Open issues0

No open issues.

Open PRs0

No open pull requests.

Fixes on record

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

  • #117626 fix(mcp): stdio command lookup stops mutating PATHEXT and reading the parent PATH (#117214 #117213, salvage #117238)

    merged to main

    files: tests/tools/test_mcp_tool_issue_948.py, tools/mcp_tool_config.py

  • #117863 hermes_platform.host: one machine-facts package, WSL/container predicates, NVIDIA ARM64 SoC recognizer (NS-920)

    merged to main

    files: AGENTS.md, hermes_cli/local_runtime/binaries.py, hermes_cli/main_desktop.py, hermes_constants.py, hermes_platform/__init__.py, hermes_platform/catalog/__init__.py, hermes_platform/host/__init__.py, hermes_platform/host/facts.py, hermes_platform/host/products.py, hermes_platform/host/runtime.py, hermes_platform/resolver/__init__.py, pyproject.toml, tests/acp_adapter/test_session.py, tests/fixtures/resolution_allowlist.json, tests/hermes_cli/test_desktop_exe_integrity.py, tests/hermes_cli/test_desktop_wsl_gpu.py, tests/hermes_cli/test_gateway_wsl.py, tests/hermes_platform/__init__.py, tests/hermes_platform/test_facts.py, tests/hermes_platform/test_import_hygiene.py (+8 more)

2 PRs closed without merging

From the close comments: done elsewhere 1 · merged via another change 1

  • #117219 fix(mcp): keep stdio command lookup inside the child env · done elsewhere → 9eca7f3, #117626
  • #117238 fix(mcp): resolve stdio commands without reading or mutating the parent env · merged via another change → 9eca7f3, #117626
Closed issues · 1
  • Closed#117213MCP stdio command lookup falls back to the parent's PATH when the server env has no PATH
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 0.40: 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

Merged PRs
#117626, #117863
Closed issues
1
Attempts
2 PRs closed without merging
Fix link checked
22 Sep 2026

For your agent

The same facts, typed.

cluster/117213.json
cluster/117213.md