# Pre Compact

> Compact prep + come-back prompt (compact-M)

- Skill: `mathcaz/pre-compact` (Agent Skill)
- Install (CLI): `npx skillmds@latest add mathcaz/pre-compact`
- Raw SKILL.md: https://api.skillmd.com/api/skills/mathcaz/pre-compact/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: AI & ML
- Author: MathCaz (https://skillmd.com/u/mathcaz)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/mathcaz/pre-compact

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# Compact prep + come-back prompt (compact-M)

Two deliverables, in order: (1) save the full session state to a durable file, (2) print a self-sufficient come-back prompt the user can paste to resume. This skill does NOT run `/compact` — the user runs it after.

Distinct from `handoff-M full` (which briefs a *fresh* agent, temp doc only). Here the point is resuming *this* line of work after compaction/session-restart, with the user's next task driving it.

## Step 1 — Save full state (durable)

Write a `resume state` capturing everything needed to continue:

- **Goal** — what this work is ultimately for (one line)
- **Where we are** — what's done, current position, what just happened
- **Key decisions** — with the load-bearing *why* (so they aren't re-litigated)
- **Constraints / gotchas** — discovered facts, dead-ends ruled out, things to avoid
- **Pointers** — relevant `file:line`, paths, PRs, tickets, queries (reference, don't paste)
- **Open threads** — unresolved items
- **Next** — the user's stated next task (verbatim from args), sharpened into concrete first steps

Location:
1. **notes-M topic active** → checkpoint into that topic's notes file (update `## Summary` + a `## Current state` entry, bump `Last updated`). This IS the notes-M "before /compact" checkpoint. Print the absolute path.
2. **No active topic** → save to the OS temp dir (e.g. `compact-resume-<slug>.md`), print the path, and note: "temp copy — want a versioned copy in your repo instead?" Don't block on the answer; the come-back prompt (Step 2) is self-sufficient regardless.

Redact secrets (keys, tokens, PII).

## Step 2 — Print the come-back prompt

Output a single fenced block the user can copy wholesale. Make it **self-sufficient** — enough inline context to resume even if the saved file is gone. Sharpen the user's raw "next" into an actionable directive, not a restatement.

```
Resume: <one-line goal>

## Where we are
<concise state: done / current position / just happened>

## Key context
<load-bearing decisions + why · constraints · gotchas · file:line pointers>

## Skills to (re)invoke
<e.g. notes-M topic at <path>; any others in play>

## Do next
<the sharpened next task → concrete first step(s)>

Full saved state: <path>
```

Keep it tight — favor pointers over pasted content. After printing, tell the user they can now run `/compact` (or start a fresh session and paste the block).

## Rules

- Come-back prompt is the primary deliverable; the saved file is the durable backup.
- Don't duplicate content that already lives in PRDs/plans/ADRs/commits — reference by path/URL.
- Sharpen "next", don't parrot it. Point to `file:line`, don't paste files.