# NousResearch/hermes-agent · MCP circuit breaker and tool budget hardening

## Open now

- 2 issues, 1 PR open on GitHub.
- #44172: \[Bug\]: MCP client hardening: no result-size cap, no per-turn call budget, reconnect/circuit-breaker constants not configurable
- #67253: \[Perf\]: No aggregate parent+subagent tool budget — Desktop catch-up turn ran 322 live tool calls before first response
- PR #68455: feat(mcp): per-server circuit breaker threshold via breaker_threshold config

These items address MCP client reliability concerns including circuit breaker miscategorization of semantic errors, configurable per-server breaker thresholds, and missing limits on result size, per-turn call budgets, and reconnect constants. A related performance report describes uncapped tool call accumulation before a first response.

## TL;DR

- 6 member(s): 2 open issue(s), 0 closed issue(s), 1 open PR(s), 0 merged PR(s), 3 PR(s) closed without merging.
- No fix has been merged to main; one or more PRs were attempted (see below).
- **Recommended:** review the prior/competing PR(s) below. A fix was attempted but not merged; your case may extend or revive that work.

## Maintainer resolution verdict

- Internal-tracker verdict over this cluster's issue members: `unresolved`. This is distinct from the fix status above. Weigh it yourself.

## How this cluster was grouped

- Link evidence (`STRUCTURAL_PARTIAL`): some members are connected by structural evidence (shared changed files, or a closing/superseded reference); the rest are joined by an automated relevance judgement over their text.
- Members outside that structural core may belong to a different underlying problem.
- Pairwise link density `0.29`: 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.

## Open related issues

- #44172: \[Bug\]: MCP client hardening: no result-size cap, no per-turn call budget, reconnect/circuit-breaker constants not configurable
- #67253: \[Perf\]: No aggregate parent+subagent tool budget — Desktop catch-up turn ran 322 live tool calls before first response

## Prior & competing PRs

- **#61555: fix(mcp): semantic tool errors must not trip circuit breaker**. closed without merge
  - maintainer direction: category `implemented_elsewhere`; implication `superseded`; refs `#109114`, `#74045`, `#75511`, `#11128`
- **#68455: feat(mcp): per-server circuit breaker threshold via breaker_threshold config**. open
  - maintainer direction: category `partial_fix`; implication `needs_llm`; refs `#44172`
  - files: `tests/tools/test_mcp_circuit_breaker.py`, `tools/mcp_tool.py`
- **#74045: fix(tools): stop counting app-level MCP tool errors as server unreachability**. closed without merge
  - maintainer direction: category `uncategorized`; implication `needs_llm`; refs `#10447`, `#109180`, `#109245`
- **#121227: fix(agent): bound delegated tool fan-out per turn**. closed without merge
  - maintainer direction: category `stale_abandoned`; implication `active`; refs `0f2fdc2757f79695d60048c1a4ec3ded7b107be6`, `2304bf25ff`, `5747548f63a062426536edf14f2e24c26eb7f620`

## Fix status

- No merged fix on record.
- Subsystem: `agent`