# Compress a worklog without losing signal

> Turn messy session notes into a dense developer journal while preserving decisions, commands, and evidence.

A skill for turning verbose session notes into a dense, time-blocked developer journal. The rule that defines it: compression is non-destructive — every fact, reference, and relationship survives.

```md title="skills/compress-worklog/SKILL.md"
---
name: compress-worklog
description: Use when compressing or journaling work logs / session notes into a dense developer journal entry. Triggers on 'compress this log', 'journal this', 'maximum non-destructive compression'.
---

Use when compressing or journaling work logs / session notes into a dense developer journal entry. Triggers on 'compress this log', 'journal this', 'maximum non-destructive compression'.

Key steps & rules:

1. ZERO information loss: keep ALL facts, refs, verbs, relationships. Compression is non-destructive.
2. Drop articles/prepositions/filler; use developer shorthand (conf, env, MR, impl, perm, repo, deploy).
3. Group same-subject entries into one time-blocked entry.
4. Preserve the `## timestamp | branch` header format. Chronological order, oldest to newest.
5. No prose, no preamble, no commentary — output raw compressed signal only.
6. Include a short shorthand glossary as reference material in the skill.
```

### Compress the form, not the facts

The distinction at the core of this skill: drop articles, prepositions, and filler, but never drop a fact, reference, or relationship. The output is shorter because the prose is gone, not because anything was summarized away.

### Signal only

Rule 5 keeps the output usable as a log — raw compressed signal, no preamble or commentary — while the shorthand glossary makes the abbreviations decodable later.

<Principle title="Compression must not change the facts">
  A useful worklog gets denser without losing relationships, commands, branches, timestamps, or
  decisions. If a future reader cannot reconstruct the work, it was summarized too hard.
</Principle>

### Why it matters for long sessions

Long agent sessions lose value when the useful facts are buried in chat residue. Compression keeps
the audit trail small enough to reuse without flattening cause and effect.

The output should still answer: what changed, what command proved it, what failed, what decision was
made, and where the next person should resume.