Open source, all the way down

SDKs, widget, CLI, and the feedback-collection skill are Apache-licensed. Our API definitions are open too — if Coolhand's managed backend ever isn't what you want, point everything at your own instead. Nothing is trapped.

The feedback-collection skill

Our flagship open-source tool audits your codebase and tells you where and how to start collecting high-signal human feedback — starting with what's already there. Instead of building a new annotation pipeline, it looks for signal you're already generating: edits users make to AI output, explanations they give, actions they take instead of accepting a suggestion. Once passive capture is in place, it helps you graduate to richer, purpose-built prompts over time.

View the feedback-collection skill on GitHub

SDKs

Ruby

Zero-config LLM monitoring for Ruby apps

# Gemfile

gem 'coolhand'

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Python

Zero-config LLM monitoring for Python apps

# Install

pip install coolhand

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Node.js

Zero-config LLM monitoring for Node.js

# Install

npm install coolhand-node

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coolhand-js widget

Drop-in feedback widget for any web app. No SDK required.

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CLI

Inspect logs, replay requests, and manage optimizations from the terminal.

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See the feedback widget and review workflow in action.

View the feedback demo

Nothing is trapped

Every SDK, the widget, and the skill work without Coolhand's managed backend. Our API definitions are open, so you can stand up your own simple backend and point every tool at it directly. If Coolhand ever isn't the right fit, you're not disentangling anything — you're just changing a URL.