# NousResearch/hermes-agent · Skills prompt cache invalidation bug and fixes

## Open now

- Nothing open on GitHub.

A bug where newly installed skills are invisible to a running gateway due to stale in-process skill prompt caching with no cross-process invalidation. Multiple fix attempts address this by including the skills manifest in the cache key and invalidating the skills LRU cache when the skills directory changes.

## TL;DR

- 6 member(s): 0 open issue(s), 1 closed issue(s), 0 open PR(s), 1 merged PR(s), 4 PR(s) closed without merging.
- A fix was merged to main in PR #118661. Verify it addresses your case.
- **Recommended:** read PR #118661 (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: `unresolved`. 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evidence (`STRUCTURAL_SPANNING`): every member is connected by structural evidence: shared changed files, or a closing/superseded reference.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 `0.33`: 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

- #92313: Newly installed skills invisible to running gateway: stale in-process _SKILLS_PROMPT_CACHE (no cross-process invalidation)

## Prior & competing PRs

- **#118661: Skills added mid-conversation reach the model on every surface, prompt cache kept (port cloudflare-os#267, fixes #92313)**. merged to main · fix tier `verified`
  - maintainer direction: category `merged`; implication `superseded`
  - files: `agent/prompt_builder.py`, `agent/skills_index_delta.py`, `agent/turn_context.py`, `hermes_cli/plugins_activation_live.py`, `tests/agent/test_skills_index_delta.py`, `website/docs/developer-guide/prompt-assembly.md`, `website/docs/user-guide/features/skills.md`
- **#92320: fix(prompt): invalidate skills index LRU when skills dir changes (fixes #92313)**. closed without merge
  - maintainer direction: category `implemented_elsewhere`; implication `superseded`; refs `097fcaa1de`, `c098b2bf1dd`, `#118661`
- **#94089: fix(agent): include skills manifest in prompt cache key**. closed without merge
  - maintainer direction: category `superseded_by_pr`; implication `superseded`; refs `#92320`
- **#103555: fix(agent): include skills manifest in prompt cache key (#92313)**. closed without merge
  - maintainer direction: category `superseded_by_pr`; implication `superseded`; refs `#92320`, `#92313`, `#94089`, `#92320`, `#92320`
- **#106230: fix(prompt): invalidate skills LRU when skills dir changes (rebased from #92320)**. closed without merge
  - maintainer direction: category `implemented_elsewhere`; implication `superseded`; refs `097fcaa1de`, `c098b2bf1dd`, `#118661`

## Fix status

- Merged to main in PR #118661 (cited above). No release data is tracked. Verify downstream.
- Fix last verified (merged) `2026-10-10`.
- Subsystem: `agent`