context-optimization

name	context-optimization
description	Use when managing context window usage, compressing long sessions, or optimizing token usage. Triggers on keywords like "context", "memory", "tokens", "compress", "summarize session", "context limit", "optimize context".
allowed-tools	Read, Write, Edit, Bash, Grep, Glob, TodoWrite, mcp__memory__*
infer	true

Context Optimization & Management

Manage context window efficiently to maintain productivity in long sessions.

---

Context Architecture

┌─────────────────────────────────────────────────────────────┐
│                     Context Window (~200K tokens)           │
├─────────────────────────────────────────────────────────────┤
│ System Prompt (CLAUDE.md excerpts)          ~2,000 tokens   │
│ ─────────────────────────────────────────────────────────── │
│ Working Memory (current task state)         ~10,000 tokens  │
│ ─────────────────────────────────────────────────────────── │
│ Retrieved Context (RAG from codebase)       ~20,000 tokens  │
│ ─────────────────────────────────────────────────────────── │
│ Episodic Memory (past session learnings)    ~5,000 tokens   │
│ ─────────────────────────────────────────────────────────── │
│ Tool Descriptions (relevant tools only)     ~3,000 tokens   │
└─────────────────────────────────────────────────────────────┘

---

Four Context Strategies

1. Writing (Save Important Context)

Save critical findings to persistent memory:

// After discovering important patterns or decisions
mcp__memory__create_entities([
    {
        name: 'EmployeeValidation',
        entityType: 'Pattern',
        observations: ['Uses PlatformValidationResult fluent API', 'Async validation via ValidateRequestAsync', 'Found in Growth.Application/UseCaseCommands/']
    }
]);

When to Write:

• Discovered architectural patterns
• Important business rules
• Cross-service dependencies
• Solution decisions

2. Selecting (Retrieve Relevant Context)

Load relevant memories at session start:

// Search for relevant patterns
mcp__memory__search_nodes({ query: 'Employee validation pattern' });

// Open specific entities
mcp__memory__open_nodes({ names: ['EmployeeValidation', 'GrowthService'] });

When to Select:

• Starting a related task
• Continuing previous work
• Cross-referencing patterns

3. Compressing (Summarize Long Trajectories)

Create context anchors every 10 operations:

=== CONTEXT ANCHOR ===
Current Task: Implement employee leave request feature
Completed:

- Created LeaveRequest entity with validation
- Added SaveLeaveRequestCommand with handler
- Implemented entity event handler for notifications

Remaining:

- Create GetLeaveRequestListQuery
- Add controller endpoint
- Write unit tests

Key Findings:

- Leave requests use GrowthRootRepository
- Notifications via entity event handlers, not direct calls
- Validation uses PlatformValidationResult.AndAsync()

# Next Action: Create query handler with GetQueryBuilder pattern

4. Isolating (Use Sub-Agents)

Delegate specialized tasks to sub-agents:

// Explore codebase (reduced context)
Task({ subagent_type: 'Explore', prompt: 'Find all entity event handlers in Growth service' });

// Plan implementation (focused context)
Task({ subagent_type: 'Plan', prompt: 'Plan leave request approval workflow' });

When to Isolate:

• Broad codebase exploration
• Independent research tasks
• Parallel investigations

---

Context Anchor Protocol

Every 10 operations, write a context anchor:

1. Re-read original task from todo list or initial prompt
2. Verify alignment with current work
3. Write anchor summarizing progress
4. Save to memory if discovering important patterns

=== CONTEXT ANCHOR [10] ===
Task: [Original task description]
Phase: [Current phase number]
Progress: [What's been completed]
Findings: [Key discoveries]
Next: [Specific next step]
Confidence: [High/Medium/Low]
===========================

---

Token-Efficient Patterns

File Reading

// ❌ Reading entire files
Read({ file_path: 'large-file.cs' });

// ✅ Read specific sections
Read({ file_path: 'large-file.cs', offset: 100, limit: 50 });

// ✅ Use grep to find specific content first
Grep({ pattern: 'class SaveEmployeeCommand', path: 'src/' });

Search Optimization

// ❌ Multiple sequential searches
Grep({ pattern: 'CreateAsync' });
Grep({ pattern: 'UpdateAsync' });
Grep({ pattern: 'DeleteAsync' });

// ✅ Combined pattern
Grep({ pattern: 'CreateAsync|UpdateAsync|DeleteAsync', output_mode: 'files_with_matches' });

Parallel Operations

// ✅ Parallel reads for independent files
[Read({ file_path: 'file1.cs' }), Read({ file_path: 'file2.cs' }), Read({ file_path: 'file3.cs' })];

---

Memory Management Commands

Save Session Summary

// Before ending session or hitting limits
const summary = {
    task: 'Implementing employee leave request feature',
    completed: ['Entity', 'Command', 'Handler'],
    remaining: ['Query', 'Controller', 'Tests'],
    discoveries: ['Use entity events for notifications'],
    files: ['LeaveRequest.cs', 'SaveLeaveRequestCommand.cs']
};

// Save to memory
mcp__memory__create_entities([
    {
        name: `Session_${new Date().toISOString().split('T')[0]}`,
        entityType: 'SessionSummary',
        observations: [JSON.stringify(summary)]
    }
]);

Load Previous Session

// At session start
mcp__memory__search_nodes({ query: 'Session leave request' });

---

Anti-Patterns

Anti-Pattern	Better Approach
Reading entire large files	Use offset/limit or grep first
Sequential searches	Combine with OR patterns
Repeating same searches	Cache results in memory
No context anchors	Write anchor every 10 ops
Not using sub-agents	Isolate exploration tasks
Forgetting discoveries	Save to memory entities

---

Quick Reference

Token Estimation:

• 1 line of code ≈ 10-15 tokens
• 1 page of text ≈ 500 tokens
• Average file ≈ 1,000-3,000 tokens

Context Thresholds:

• 50K tokens: Consider compression
• 100K tokens: Required compression
• 150K tokens: Critical - save and summarize

Memory Commands:

• mcp__memory__create_entities - Save new knowledge
• mcp__memory__search_nodes - Find relevant context
• mcp__memory__add_observations - Update existing entities