/neo:gc — collect stale memory

Scan: !bash "${CLAUDE_PLUGIN_ROOT}/hooks/scripts/brain-gc.sh" 2>/dev/null || echo "scan unavailable — read .neo/brain/LESSONS.md and review manually"

Steps

1. Guard: if .neo/brain/ is missing, stop and point to /neo:init. Check DECISIONS.md: for each entry, test its Reverses when: condition against the codebase/git and note any that are currently true. If the scan above reports healthy (no dead anchors, no aged, no undated) AND no decision is reversed, report "Brain healthy — nothing to collect" and stop.

2. Spawn neo-shadow (Agent tool) with the 6-section contract. TASK: review ONLY the flagged lesson entries from the scan plus the decisions NEO found reversed (quoted) against the current codebase, one verdict each. For a reversed decision: KEEP (condition misjudged — say why) or ARCHIVE (move the whole entry to .neo/brain/archive/DECISIONS.md under a ## YYYY-MM-DD heading with a one-line reason; create the file if absent). For lessons:

   • KEEP — still true. For UNDATED entries, stamp today's date and the default provenance tag: - [YYYY-MM-DD] [observed] <unchanged text>. For AGED entries confirmed still true, refresh the datestamp (date = last confirmed).
   • REWRITE — the kernel is true but details drifted (file moved, command renamed). Update text, anchor, and datestamp. A DEAD-ANCHOR often means the file moved — grep for its new location before concluding it's gone.
   • ARCHIVE — no longer applies (dependency removed, pattern retired). Move the line to .neo/brain/archive/LESSONS.md under a ## YYYY-MM-DD heading with a one-line reason. Create the archive file if absent.

   EXPECTED OUTCOME: every remaining LESSONS.md entry datestamped and true against the current codebase; archived entries preserved verbatim with reasons. MUST NOT: delete any entry outright (archive instead), touch entries the scan did not flag or decisions NEO did not quote, touch anything outside .neo/brain/. CONTEXT: the full scan report above, the quoted reversed decisions, plus the current date.

3. Verify + report: from the shadow's report, relay one line: "GC done — N kept, N rewritten, N archived; decisions: N kept, N archived." If the shadow was unsure about any entry, it keeps it marked (unverified) — surface those to the user for a human call.