Cairn

MoA aggregator prompt cache billing and routing fixes

NousResearch/hermes-agent · cluster 112358

Data as of

Nothing open on GitHub. Fix merged in #113175. Check it covers your case.

The short answer

0open issues
0open PRs
6items grouped
Known?
Yes. 6 related items grouped here, 1 issue already closed.
Fix event
A fix was merged to main in PR #113175. Check it covers your case. No release data is tracked.
Tracker
The maintainers' tracker marks this resolved, deciding PR #115606. That is separate from the fix event.
Still open
Nothing open on GitHub.

Multiple fixes targeting how the MoA aggregator handles prompt cache identity, routing, and persistence across tool steps and iterations. A related issue documents unexpected re-billing behavior when tool history grows and cache fails to stay pinned to the system prompt.

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.

  • #113175 fix(moa): aggregator prompt cache no longer collapses to the system prompt on every tool step (#112358)

    merged to main

    files: agent/moa_loop.py, tests/agent/test_failover_identity.py, tests/agent/test_moa_aggregator_prefix_stability.py, website/docs/user-guide/features/mixture-of-agents.md

  • #113784 fix(moa): Anthropic-wire aggregator keeps the cache prefix through the task on iteration 1 (closes remaining atoms of #112358)

    merged to main

    files: agent/anthropic_message_convert.py, agent/moa_loop.py, tests/agent/test_anthropic_adapter.py, tests/agent/test_moa_aggregator_prefix_stability.py, website/docs/user-guide/features/mixture-of-agents.md

  • #115606 fix(moa): aggregator recovers from strict-alternation 400s per destination (closes remaining atoms of #112358)

    merged to main

    files: agent/chat_completion_helpers.py, agent/error_classifier.py, agent/moa_alternation.py, agent/moa_loop.py, agent/turn_failure_copy.py, tests/agent/test_error_classifier.py, tests/agent/test_moa_alternation_recovery.py, website/docs/user-guide/features/mixture-of-agents.md

2 PRs closed without merging

From the close comments: done elsewhere 2

  • #112360 fix(moa): preserve Nous aggregator cache routing · done elsewhere → 0265514, 170d616, #112358, #113175, #113784
  • #112400 fix(moa): reuse transport cache identity for Nous aggregator calls · done elsewhere → 0265514, 170d616, #112358, #113175, #113784
Closed issues · 1
  • Closed#112358MoA aggregator: prompt cache hits stay pinned to the system prompt; growing tool history re-billed every call (~$147 in 49 min)
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

Merged PRs
#113175, #113784, #115606
Closed issues
1
Attempts
2 PRs closed without merging
Fix link checked
19 Sep 2026

For your agent

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cluster/112358.json
cluster/112358.md