Strategic Compact Skill

Suggests manual /compact at strategic points in your workflow rather than relying on arbitrary auto-compaction.

When to Activate

• Running long sessions that approach context limits (200K+ tokens)
• Working on multi-phase tasks (research → plan → implement → test)
• Switching between unrelated tasks within the same session
• After completing a major milestone and starting new work
• When responses slow down or become less coherent (context pressure)

Why Strategic Compaction?

Auto-compaction triggers at arbitrary points:

• Often mid-task, losing important context
• No awareness of logical task boundaries
• Can interrupt complex multi-step operations

Strategic compaction at logical boundaries:

• After exploration, before execution — Compact research context, keep implementation plan
• After completing a milestone — Fresh start for next phase
• Before major context shifts — Clear exploration context before different task

How It Works

The suggest-compact.js script runs on PreToolUse (Edit/Write) and:

1. Tracks tool calls — Counts tool invocations in session
2. Threshold detection — Suggests at configurable threshold (default: 50 calls)
3. Periodic reminders — Reminds every 25 calls after threshold

Hook Setup

Add to your ~/.codex/settings.json:

{
  "hooks": {
    "PreToolUse": [
      {
        "matcher": "Edit",
        "hooks": [{ "type": "command", "command": "node ~/.codex/skills/strategic-compact/suggest-compact.js" }]
      },
      {
        "matcher": "Write",
        "hooks": [{ "type": "command", "command": "node ~/.codex/skills/strategic-compact/suggest-compact.js" }]
      }
    ]
  }
}

Configuration

Environment variables:

• COMPACT_THRESHOLD — Tool calls before first suggestion (default: 50)

Compaction Decision Guide

Use this table to decide when to compact:

What Survives Compaction

Understanding what persists helps you compact with confidence:

Best Practices

1. Compact after planning — Once plan is finalized in TodoWrite, compact to start fresh
2. Compact after debugging — Clear error-resolution context before continuing
3. Don't compact mid-implementation — Preserve context for related changes
4. Read the suggestion — The hook tells you when, you decide if
5. Write before compacting — Save important context to files or memory before compacting
6. Use `/compact` with a summary — Add a custom message: /compact Focus on implementing auth middleware next

Related

• The Longform Guide — Token optimization section
• Memory persistence hooks — For state that survives compaction
• continuous-learning skill — Extracts patterns before session ends