# NousResearch/hermes-agent · Split skill message cache into stable/volatile parts

## Open now

- Nothing open on GitHub.

These issues and PRs address a caching inefficiency where volatile tail bytes in skill invocation messages invalidate the entire cached prefix. The work involves declaring stable/volatile boundaries on skill turns so static prefixes can be reused across webhook events.

## TL;DR

- 5 member(s): 0 open issue(s), 1 closed issue(s), 0 open PR(s), 1 merged PR(s), 3 PR(s) closed without merging.
- A fix was merged to main in PR #82423. Verify it addresses your case.
- **Recommended:** read PR #82423 (and any competing PRs below) before filing. Confirm the merged change covers your symptom.

## Maintainer resolution verdict

- Internal-tracker verdict over this cluster's issue members: `resolved` · deciding PR(s): `pr-82423`. This is distinct from the fix status above. Weigh it yourself.

## How this cluster was grouped

- Link evidence (`STRUCTURAL_SPANNING`): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.
- Pairwise link density `0.40`: 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.

## Closed / duplicate issues

- #81867: Webhook/skill-invocation user messages cache as one atomic block — volatile tail bytes invalidate the entire static prefix

## Prior & competing PRs

- **#82423: perf(cache): split skill turns at a builder-declared stable/volatile boundary**. merged to main · fix tier `verified`
  - maintainer direction: category `merged`
  - files: `agent/prompt_cache_boundary.py`, `agent/prompt_caching.py`, `agent/skill_commands.py`, `cron/scheduler.py`, `tests/agent/test_prompt_cache_boundary.py`
- **#81928: perf(cache): reuse static skill prefixes across webhook events**. closed without merge
  - maintainer direction: category `superseded_by_pr`; implication `superseded`; refs `#82423`, `#82049`, `#81867`
- **#81929: fix(agent): declare skill cache boundaries on the message**. closed without merge
  - maintainer direction: category `superseded_by_pr`; implication `superseded`; refs `#82423`, `#82049`, `#81867`
- **#82049: perf(cache): split skill turns at a builder-declared stable/volatile boundary**. closed without merge
  - maintainer direction: category `merged_via`; implication `superseded`; refs `#82423`, `#81928`, `#81929`

## Fix status

- Merged to main in PR #82423 (cited above). No release data is tracked. Verify downstream.
- Fix last verified (merged) `2026-08-09`.