Performance Optimization

Model Selection Strategy

Haiku 4.5 (90% of Sonnet capability, 3x cost savings):

  • Lightweight agents with frequent invocation
  • Pair programming and code generation
  • Worker agents in multi-agent systems

Sonnet 4.5 (Best coding model):

  • Main development work
  • Orchestrating multi-agent workflows
  • Complex coding tasks

Opus 4.5 (Deepest reasoning):

  • Complex architectural decisions
  • Maximum reasoning requirements
  • Research and analysis tasks

Context Window Management

Avoid last 20% of context window for:

  • Large-scale refactoring
  • Feature implementation spanning multiple files
  • Debugging complex interactions

Lower context sensitivity tasks:

  • Single-file edits
  • Independent utility creation
  • Documentation updates
  • Simple bug fixes

Ultrathink + Plan Mode

For complex tasks requiring deep reasoning:

  1. Use ultrathink for enhanced thinking
  2. Enable Plan Mode for structured approach
  3. "Rev the engine" with multiple critique rounds
  4. Use split role sub-agents for diverse analysis

Build Troubleshooting

If build fails:

  1. Use build-error-resolver agent
  2. Analyze error messages
  3. Fix incrementally
  4. Verify after each fix