/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
- 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
Thesuggest-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:
Compaction Decision Guide
What Survives Compaction
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
/compactwith a summary — Add a custom message:/compact Focus on implementing auth middleware next
Context compaction is a powerful tool, but timing matters. Compact at logical boundaries to preserve what matters.