sagargupta16/context-management

Context Management

Quick Reference

| Signal | Action | |--------|--------| | At ~50% context usage | Manual /compact with focus instructions | | Approach fails, output quality drops | /rewind to before the failed attempt | | New unrelated task mid-session | /clear or start new session | | Need to explore/research | Spawn sub-agent (keeps main context clean) | | Over 300K tokens used | Strongly consider new session | | Auto-compact triggered | Too late -- quality already degraded |

Context Rot

Context rot is the gradual degradation of output quality as the context window fills up. It typically starts around 300-400K tokens (on 1M token models), but varies by task complexity.

Symptoms

• Claude repeats previous mistakes or ignores corrections
• Output becomes more generic, less project-specific
• Instructions from CLAUDE.md start being ignored
• Code patterns drift from established conventions

Prevention

1. Manual compact at 50% -- don't wait for auto-compaction
2. Use sub-agents for exploration tasks (research stays in child context, only results bubble up)
3. New session for new tasks -- don't carry unrelated context
4. Focus compaction: /compact "keep only the auth implementation details and test results"

Branching Strategy

Every turn in a Claude Code session is a branching point. Choose deliberately:

Current turn outcome:
├── Good result → Continue (carry all context forward)
├── Mediocre result → Two options:
│   ├── /rewind (drop the attempt, retry clean)
│   └── Correct in context (adds noise, sometimes fine for small fixes)
├── Bad result / wrong direction → /rewind (always)
├── Task complete, new task → /clear or new session
└── Need deep research → Spawn sub-agent

/rewind vs Correct In Context

| Scenario | Use /rewind | Correct in context | |----------|------------|-------------------| | Wrong approach entirely | Yes | No | | Small typo or missed detail | No | Yes | | Generated wrong file | Yes | No | | Right idea, minor adjustment | No | Yes | | Multiple failed attempts | Yes (go back further) | No |

Compaction

When to Compact

• Good time: ~50% context usage, between logical task boundaries
• Bad time: Mid-implementation, during debugging, during a complex multi-step plan

How to Compact Well

# BAD: no guidance
/compact

# GOOD: focused compaction with retention instructions
/compact "Keep: current implementation plan steps 3-7, test results from auth module, the API schema we agreed on. Drop: exploration of rejected approaches, file reads from unrelated modules."

Compaction vs Clear vs New Session

| Method | Preserves | Loses | Best For | |--------|-----------|-------|----------| | /compact | Summary of work, key decisions | Details, exact code snippets | Mid-task context reduction | | /clear | Nothing (clean slate) | Everything | Starting fresh task in same session | | New session | Nothing | Everything | Completely new task or severely degraded context |

Sub-Agent Isolation

Use sub-agents to keep the main context window clean:

| Task Type | Use Sub-Agent? | Why | |-----------|---------------|-----| | File exploration / grep | Yes | Search results are bulky, only need the answer | | Code review | Yes | Review details stay in child, summary comes back | | Research / investigation | Yes | Exploration paths stay isolated | | Implementation | No | Need to see and verify the changes | | Debugging | Depends | Simple bug: no. Complex investigation: yes |

Pattern: Research Then Implement

1. Spawn sub-agent: "Research how auth middleware works in this codebase"
2. Get summary back (main context stays clean)
3. Implement based on summary (in main context where you can verify)

Anti-Patterns

| Anti-Pattern | Problem | Do Instead | |-------------|---------|-----------| | Never compacting | Context fills up, quality degrades silently | Compact at ~50% usage | | Compacting too often | Lose important context | Compact at natural boundaries | | Waiting for auto-compact | Model is least intelligent during auto-compact | Manual compact before it triggers | | Saying "no try again" after bad output | Failed attempt stays in context, pollutes future attempts | /rewind then re-prompt | | Reading every file "just in case" | Wastes context on irrelevant content | Search first, read only what's needed | | Running all research in main context | Exploration results bloat context | Use sub-agents for research | | Continuing after multiple failures | Context is poisoned with failed approaches | /clear or new session |