Pi Agent Core vs Stirrup

Pi Agent Core and Stirrup are both agent frameworks. Pi Agent Core is published by Earendil and Stirrup by ArtificialAnalysis. On GitHub, Pi Agent Core has 117,586 stars and Stirrup has 667. Both were last active in Oct 2026. The table lines up where they differ (publisher, GitHub stars, weekly downloads and languages) and has the install commands for both. Everything here comes from the listings' public sources and is refreshed daily. Pi Agent Core describes itself as: Minimal TypeScript agent harness with an agent runtime, multi-provider LLM API, terminal UI and coding agent CLI that users extend themselves. Stirrup: Lightweight Python framework and starting template for agents that let the model choose its own approach to each task. Licenses: Pi Agent Core MIT, Stirrup MIT.