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:

• Tracks tool calls — Counts tool invocations in session

• Threshold detection — Suggests at configurable threshold (default: 50 calls)

• Periodic reminders — Reminds every 25 calls after threshold

Hook Setup

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

{

  "hooks": {

    "PreToolUse": [

      {

        "matcher": "Edit",

        "hooks": [{ "type": "command", "command": "node ~/.claude/scripts/hooks/suggest-compact.js" }]

      },

      {

        "matcher": "Write",

        "hooks": [{ "type": "command", "command": "node ~/.claude/scripts/hooks/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:

Phase Transition

Compact?

Why

Research → Planning

Yes

Research context is bulky; plan is the distilled output

Planning → Implementation

Yes

Plan is in TodoWrite or a file; free up context for code

Implementation → Testing

Maybe

Keep if tests reference recent code; compact if switching focus

Debugging → Next feature

Yes

Debug traces pollute context for unrelated work

Mid-implementation

No

Losing variable names, file paths, and partial state is costly

After a failed approach

Yes

Clear the dead-end reasoning before trying a new approach

What Survives Compaction

Understanding what persists helps you compact with confidence:

Persists

Lost

CLAUDE.md instructions

Intermediate reasoning and analysis

TodoWrite task list

File contents you previously read

Memory files (~/.claude/memory/)

Multi-step conversation context

Git state (commits, branches)

Tool call history and counts

Files on disk

Nuanced user preferences stated verbally

Best Practices

• Compact after planning — Once plan is finalized in TodoWrite, compact to start fresh

• Compact after debugging — Clear error-resolution context before continuing

• Don't compact mid-implementation — Preserve context for related changes

• Read the suggestion — The hook tells you when, you decide if

• Write before compacting — Save important context to files or memory before compacting

• **Use /compact with a summary** — Add a custom message: /compact Focus on implementing auth middleware next

Token Optimization Patterns

Trigger-Table Lazy Loading

Instead of loading full skill content at session start, use a trigger table that maps keywords to skill paths. Skills load only when triggered, reducing baseline context by 50%+:

Trigger

Skill

Load When

"test", "tdd", "coverage"

tdd-workflow

User mentions testing

"security", "auth", "xss"

security-review

Security-related work

"deploy", "ci/cd"

deployment-patterns

Deployment context

Context Composition Awareness

Monitor what's consuming your context window:

• CLAUDE.md files — Always loaded, keep lean

• Loaded skills — Each skill adds 1-5K tokens

• Conversation history — Grows with each exchange

• Tool results — File reads, search results add bulk

Duplicate Instruction Detection

Common sources of duplicate context:

• Same rules in both ~/.claude/rules/ and project .claude/rules/

• Skills that repeat CLAUDE.md instructions

• Multiple skills covering overlapping domains

Context Optimization Tools

• token-optimizer MCP — Automated 95%+ token reduction via content deduplication

• context-mode — Context virtualization (315KB to 5.4KB demonstrated)

Related

• The Longform Guide — Token optimization section

• Memory persistence hooks — For state that survives compaction

• continuous-learning skill — Extracts patterns before session ends