Cairn

Tool-call argument truncation during compaction

NousResearch/hermes-agent · cluster 110094 · agent

Data as of

3 open items. Fix merged in #125036. Check it covers your case.

The short answer

1open issue
2open PRs
6items grouped
Known?
Yes. 6 related items grouped here, 0 issues already closed.
Fix event
A fix was merged to main in PR #125036. 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
1 issue and 2 PRs.

These issues and PRs concern a bug where compaction silently truncates tool-call argument strings to 200 characters with no tail preserved, and efforts to make the truncation behavior configurable and less destructive.

Open issues1

  • Issue#110094Compaction silently destroys tool-call arguments: every string leaf cut to 200 chars, no tail kept, no config surface

Open PRs2

  • PR#110105fix(context): stop compaction from destroying tool argument history
  • PR#110141fix(compression): keep a tail window when truncating tool-call args (#110094)

Fixes on record

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

  • #125036 fix(context): stop compaction from rewriting old tool-call arguments

    merged to main

    files: agent/compression_marker.py, agent/context_compressor.py, tests/agent/test_context_compressor.py, tests/agent/test_tool_call_guardrail_runtime.py, website/docs/user-guide/configuration.md

2 PRs closed without merging

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

  • #110101 fix(agent): preserve tool-call argument tails during compaction · merged via another change → #125036, #110094
  • #110107 feat(compression): make tool-call argument shrinking configurable (tool_arg_head_chars / tool_arg_min_chars) · done elsewhere → 5952e95
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(structural links throughout): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.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 0.33: 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
agent
Merged PRs
#125036
Closed issues
0
Attempts
2 PRs closed without merging
Fix link checked
27 Sep 2026

For your agent

The same facts, typed.

cluster/110094.json
cluster/110094.md