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NousResearch/hermes-agent

MCP reconnect and cancellation error handling fixes

Cluster 9930 · mcp. Data as of

Nothing open on GitHub. Fix merged in #21318 on 7 May 2026. 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 #21318. Check it covers your case. No release data is tracked.
Tracker
The maintainers' tracker marks this resolved, deciding PR #21276. That is separate from the fix event.
Still open
Nothing open on GitHub.

These issues and PRs address asyncio.CancelledError leaking or causing failures during MCP reconnection and discovery, particularly on Python 3.11+, plus a related CLI fix to catch BaseException on shutdown to suppress stray tracebacks.

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.

  • #21318 fix(mcp): re-raise CancelledError explicitly in MCPServerTask.run

    merged to main

    files: tests/tools/test_mcp_cancelled_error_propagation.py, tools/mcp_tool.py

  • #21276 fix(mcp): clear stale thread interrupt before MCP discovery

    merged to main

    files: scripts/release.py, tools/mcp_tool.py

2 PRs closed without merging

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

  • #9994 fix(mcp): handle asyncio.CancelledError in reconnect loop on Python 3.11+ · done elsewhere → e0a2b08, #21318, #9930
  • #10287 fix(mcp): clear stale thread interrupt before MCP discovery · merged via another change → 46d1fc1, #21276, #9930
Closed issues · 1
  • Closed#9930MCP reconnect fails with asyncio.CancelledError on Python 3.11+
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(structural links throughout): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.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

Subsystem
mcp
Merged PRs
#21318, #21276
Closed issues
1
Attempts
2 PRs closed without merging
Fix link checked
7 May 2026

For your agent

The same facts, typed.

cluster/9930.json
cluster/9930.md