Open-Source AI Tools
Free tools for builders
The same tools I use in my own builds, for shaping specs, designing real apps, and running AI loops that ship.
Free to use or adapt.
PRD Creator
An agent skill to help you plan a new product's PRD and build-ready milestone prompts & tracking for your agent's build out.
Skill Builder
The agent skill that builds your agent skills. It interviews you about any repeatable process, then designs, writes, and verifies a well-structured skill, portable across Claude Code, Codex, Cursor, and any other agent.
Design System
An agent skill that implements a robust, customizable design system in your app. It sets up a preview & docs page and instructs your agents on how to adhere to it when building UI.
Build New
A Rails-based starter template for kicking off new apps. Pre-wired with the patterns I reach for on every project, so you can skip the boilerplate and start building.
agentcanon
A convention that gives your agent skills and instructions one canonical home, .agents/skills/ and AGENTS.md, with symlinks pointing every AI tool at it, so you stop maintaining copies that drift.
Favicon Creator
An agent skill that generates a complete favicon set (SVG, multi-resolution .ico, PNGs, Apple touch icon) from any icon and wires the meta tags into your codebase.
Agent OS
Capture and apply your own coding standards across every agent build. A lightweight, language-agnostic system that helps your AI agents build the way you would.
Design OS
Plan and design real apps using a system built for AI builders. Generates components, screens, and design specs that translate cleanly into code.
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