Performance Optimization (Agent & Model)

This skill covers AI agent and model performance (which model to use, context management, build fixes). For application/code performance (React, Next.js, bundles, rendering) use vercel-react-best-practices and the granular performance skills (e.g. cache-property-access-in-loops, dynamic-imports-for-heavy-components).

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