context-compression-engineer

name	context-compression-engineer
description	Triggers: "compress this", "context bloat", "weekly rollup", "compression strategy", "summary preserving wikilinks".
when_to_use	When notes exceed the compression threshold OR daily-note rollups are due. Discipline: archive-before-rewrite; preserve every wikilink and every canonical claim.
inputs	[{"target":"a single note path | \"older-than 7d\" | \"weekly --iso-week YYYY-Www\""}]
steps	["Read the source note(s) + 00_System/Memory Lifecycle.md (compression rules).","Identify canonical claims, all wikilinks, and any privacy: client tags.","If the note has stability: canonical → REFUSE; HIGH-risk to compress.","Generate a summary ≤ 40% of the original word count.","Verify: every wikilink appears in the summary.","Verify: every canonical claim appears verbatim in the summary.","If verification fails, regenerate (up to 3 attempts) before refusing.","Move the original to _archive/<id>-original.md (NEVER rm).","Write the summary back in place with frontmatter compressed_from: [[<id>-original]].","Re-embed both the compressed summary and the archived original.","Append a metrics row to 90-Meta/metrics.ndjson."]
tools	["Read","Write","Edit","Bash(harness compress:*,harness embed:*,mv:*,find:*)"]
failure_modes	["canonical note targeted → REFUSE; HIGH-risk","verification (every wikilink preserved) fails after 3 attempts → REFUSE; surface to user","rm requested → REFUSE; archive-only",{"privacy":"client note compressed without privacy frontmatter retained → REFUSE"}]
last_validated	"2026-05-09T00:00:00.000Z"
metrics	{"invocations":0,"success_rate":null,"mean_tokens":null}
prerequisites	["memory-architect","recall"]
is_prerequisite_of	[]
links	["[[docs/MEMORY_MODEL.md]]","[[00_System/Memory Lifecycle.md]]","[[prompts/ralph-meta-chain/05-compress.md]]","[[harness/harness/compress.py]]"]
tags	["skill","specialist","compression"]

Context Compression Engineer

The role you assume when the bloated-note threshold fires or when weekly rollups are due. Discipline: append-only invariant is sacred; verify wikilink + canonical-claim preservation before mv-to-archive.

Canonical experiment

Given a 4500-word note in 30-Notes/test-bloat.md with:

• 8 wikilinks ([[A]], [[B]], ..., [[H]]),
• 2 canonical claims (stability: stable somewhere; the body contains "Decision: X" and "Decision: Y"),

the skill must:

1. Refuse if stability: canonical.
2. Generate a ≤ 1800-word summary preserving all 8 wikilinks + both "Decision: ..." lines verbatim.
3. mv original to _archive/<id>-original.md.
4. Write summary to 30-Notes/test-bloat.md with compressed_from: [[<id>-original]].
5. Re-embed both via harness embed.
6. Append metrics row with tokens_before / tokens_after / ratio.

Verification: ratio < 0.4 AND all 8 wikilinks present AND both decision lines present.