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MCP Python-SDK tool results sent twice bug

NousResearch/hermes-agent · cluster 124451 · mcp

Data as of

3 open items. Fix attempted, not merged.

The short answer

1open issue
2open PRs
5items grouped
Known?
Yes. 5 related items grouped here, 0 issues already closed.
Fix event
No fix has been merged to main. 2 PRs closed without merging; see the attempts below.
Tracker
The maintainers' tracker marks this unresolved. That is separate from the fix event.
Still open
1 issue and 2 PRs.

A bug where MCP tool results from Python-SDK servers are duplicated before reaching the model, introduced in a specific change. Multiple fix attempts address deduplication without incorrectly flattening typed values.

Open issues1

  • Issue#124451[Bug]: MCP results from Python-SDK servers (`-> str` / `-> list`) reach the model twice since #116693

Open PRs2

  • PR#124452fix(mcp): send a Python-SDK tool result once, not twice
  • PR#124493fix(mcp): dedupe SDK results without flattening typed values (#124451)

2 PRs closed without merging

From the close comments: superseded by another PR 2

  • #124484 fix(mcp): dedupe SDK results without flattening values · superseded by another PR → #124485, #124451
  • #124485 fix(mcp): dedupe SDK results without flattening values · superseded by another PR → #124484
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(structural links throughout): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.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
Closed issues
0
Attempts
2 PRs closed without merging

For your agent

The same facts, typed.

cluster/124451.json
cluster/124451.md