Context Mode

Optimize context usage. Keep what matters, compress what doesn't, preserve across sessions.

When to Use

• Context window getting full
• Starting a new session with prior work
• Need to preserve decisions across checkpoints
• Large codebase exploration consuming tokens

Context Management Strategies

1. Summarize Aggressively

Replace verbose output with concise summaries:

Bad:  Full stack trace with 50 lines
Good: "TypeError at src/api.ts:42 — missing null check on response.data.user"

Bad:  Entire file content read
Good: "File has 200 lines, key function at line 85-120, uses X pattern"

Bad:  Running every test individually
Good: "All 47 tests pass, coverage at 82%"

2. Layer Information

Organize context by relevance:

Critical (always keep):
- Current task goal
- Active blockers
- Key architectural decisions
- File paths of modified files

Important (summarize when needed):
- Prior conversation decisions
- Test results
- Code exploration findings

Ephemeral (drop when context tight):
- Full file contents (re-read on demand)
- Verbose command output
- Intermediate search results

3. Use Memory System

• Store durable facts in MEMORY.md
• Use notes.md for cross-session observations
• Reference memory instead of re-deriving
• Search memory before re-exploring

4. Parallel Context via Subagents

• Spawn subagents for heavy exploration
• Each subagent gets clean context
• Synthesize findings, not raw output
• Don't pass full conversation to every subagent

Checkpoint Discipline

At checkpoint time, ensure these are captured:

1. What was accomplished (not what was attempted)
2. Key decisions and their rationale
3. Current state of modified files
4. Blockers and how to resolve them
5. Next action (specific, not vague)

Token Budget Awareness

Rule of thumb: If you're reading it twice, summarize it once.

Session Handoff

When context is tight:

1. Write findings to notes.md or task progress
2. Summarize what's done and what's next
3. Reference specific file paths and line numbers
4. Start fresh session with focused prompt

Anti-Patterns