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AI Tool
OpenCastle
Write your AI assistant config once and use it in every assistant.
Day 43 since launch · Launched 25 August 2026
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Made by Shushant LakhyaniKnow about Shushant Lakhyani hereGet all my visual guides hereSee what I can build for youAI+Tech+No-Code+Online Business Mini GuidesJoin the newsletterBuilt with love by Shushant Lakhyani. Building bestproductivityresources.com
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What is OpenCastle?
OpenCastle compiles one source of AI assistant configuration into the formats used by GitHub Copilot, Cursor, Claude Code, OpenCode, Windsurf, Codex and Antigravity, and tells you when they fall out of sync. Run it with npx to read your repository and set things up.
Pros
- One source for many assistants
- Warns when configs drift apart
- Quick start with npx
Cons
- Aimed at developers
- Another layer to learn
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