I built a tool that measures how a website feels.

When you ask an AI agent to "make it feel like Linear", it guesses. It knows the colours from screenshots, maybe the font. It doesn't know that the headings are 64px at weight 510, that things fade in over 420ms on a specific curve, or how far a button lifts when you hover it.

relume opens the site in a real browser, scrolls it, hovers it, and records every animation frame by frame. Then it writes all of that into a skill file your agent reads before it builds.

After the agent builds, relume measures the result the same way and scores it against the original. A bike brand built in Resend's language scored 92/100. A beauty site in Cosmos's language scored 80, and motion was the weak part (44). I'm still working on that.

Works with Claude Code, Codex, Cursor, Gemini CLI and a few others. One command to install.

relume