Skill file changes (add/remove/edit) not picked up until app restart due to never-evict in-memory cache #34443

Description

When a SKILL.md file is added, removed, or edited on disk, the change is not reflected in new chat sessions. The stale skill list persists until the entire desktop application is restarted. Starting a "new session" is not sufficient.

Root cause

In \packages/core/src/skill.ts, skill discovery results are cached in an in-memory \Map\ that is never invalidated:

\\ s
const cache = new Map<string, Info[]>()

const list = Effect.fn("SkillV2.list")(function* () {
const skills = new Map<string, Info>()
for (const source of state.get().sources) {
const key = Source.key(source)
const loaded = cache.get(key) ?? (yield* load(source))
cache.set(key, loaded)
// ...
}
return Array.from(skills.values())
})
\\

• \load(source)\ scans directories and parses \SKILL.md\ files (frontmatter + body) into \Info\ objects — once per source key
• On subsequent \list()\ calls (including across new sessions), the cached result is returned unchanged
• There is no TTL, no file watcher invalidation, no cache clearing on session creation
• The desktop app runs opencode as a long-lived server process — sessions share the same in-memory cache

A developer TODO in the same file already acknowledges this gap:

\
// QUESTION(Dax): Should local skill sources invalidate on filesystem watch
// events, following the reload policy chosen for other context sources?
\\

Steps to reproduce

1. Open OpenCode Desktop
2. Create, delete, or edit a \SKILL.md\ file (e.g. in .opencode/skills/my-skill/)
3. Start a new chat session — the skill list (<available_skills>) is unchanged
4. Quit and restart the desktop app entirely — the change is now visible

Expected behavior

Skill file changes (add, remove, edit) should be reflected when starting a new session, without requiring a full application restart.

Proposed fix

At minimum, clear or invalidate the skill cache when a new session is created. Ideally, watch skill directories for filesystem changes and invalidate affected source entries on add/remove/modify events.

Environment

• OpenCode Desktop for Windows
• Also affects any setup where the opencode server process persists across sessions