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NousResearch/hermes-agent

MCP stdio server failure isolation and reconnect resilience

Cluster 50394 · mcp. Data as of

Nothing open on GitHub. Fix merged in #68660 on 21 Jul 2026. Check it covers your case.

The short answer

0open issues
0open PRs
4items grouped
Known?
Yes. 4 related items grouped here, 1 issue already closed.
Fix event
A fix was merged to main in PR #68660. 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
Nothing open on GitHub.

These issues and fixes address how a single failing stdio MCP server can destabilize the entire MCP bridge, causing healthy servers' tools to become unavailable. The work covers isolating failing servers, adding per-server circuit breakers, and improving reconnection logic to re-register tools when a server recovers.

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.

  • #68660 fix(mcp): stdio discovery cooldown, message-less transport classification, zero-connected retry latch

    merged to main

    files: contributors/emails/[redacted:email], contributors/emails/[redacted:email], hermes_cli/mcp_startup.py, tests/hermes_cli/test_mcp_startup.py, tests/test_tui_entry_mcp_owner.py, tests/tools/test_mcp_bridge_single_failure.py, tests/tools/test_mcp_resource_content.py, tests/tools/test_mcp_tool.py, tests/tools/test_mcp_tool_session_expired.py, tools/mcp_tool.py, tui_gateway/entry.py

2 PRs closed without merging

From the close comments: merged via another change 1 · other 1

  • #50482 fix(mcp): per-server connection circuit breaker to stop the restart storm (#50394) · other → 472c068
  • #50589 fix(mcp): isolate a single failing stdio server from the bridge · merged via another change → #68660
Closed issues · 1
  • Closed#50394A single failing stdio MCP server churns the whole MCP bridge — healthy servers' tools become "Unknown tool" at runtime
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(structural links throughout): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.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 0.50: 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
#68660
Closed issues
1
Attempts
2 PRs closed without merging
Fix link checked
21 Jul 2026

For your agent

The same facts, typed.

cluster/50394.json
cluster/50394.md