June 2026: Delivered the Async Multi-Agent Orchestration Cookbook for anthropics/claude-cookbooks. Introduced two scalable patterns for async multi-agent orchestration: (1) a fixed N-agent team with peer messaging through a shared hub, and (2) a lead agent that spawns, monitors, and dismisses async subagents. The work strengthens scalability, reliability, and developer onboarding for multi-agent workflows, with clear usage guidance via the Messages API. All changes shipped with thorough documentation and aligned with existing API design. No critical bugs reported; repository health remains strong as CI passes and patterns are standardized. Business impact: accelerates feature development, reduces integration risk, and provides repeatable orchestration patterns for complex agent-based tasks.