Impeccable: a design skill that helps Codex and AI agents produce better UI

Melvin Vivas · X post · 2026-09-12 · Open on X

Topics: AI Dev Tools & Productivity, AI Agents, Tool Use & MCP · Level: beginner

Summary

The creator asked what design skill to use with Codex, and Impeccable was suggested most often. Impeccable describes itself as 'the missing design vocabulary for agents': a design language that makes your AI coding harness better at UI and design work. It is open source on GitHub.

Key points

• When the creator asked which design skill to pair with Codex, Impeccable came up most often.
• Impeccable gives AI coding agents a design vocabulary so the UI they generate is better.
• It is open source (GitHub: pbakaus/impeccable) and has a website at impeccable.style.
• The creator plans to test it over the next few days, so it is still being evaluated and not yet a proven recommendation.

Resources mentioned

• Impeccable (GitHub repo pbakaus/impeccable) · repo · github.com · free
  Open-source design language that makes your AI harness (e.g. Codex) better at design.
• Impeccable website · website · impeccable.style · free
  Website for Impeccable, 'the missing design vocabulary for agents'.
• Impeccable (@impeccable_ai) · tool · x.com · free
  A design add-on for AI coding agents, installed with `npx impeccable install`, that improves the quality of the UI/frontend designs they generate.
  Also in: Improving Codex's UI Design Output with Impeccable (npx impeccable install) (Melvin Vivas on X · notes)
• OpenAI Codex · tool · openai.com · paid
  OpenAI's coding agent. In the diagram it writes code, fixes review findings and drives the build loop. The creator also used it to make this video.
  Also in: An agent bot that installs and drives Codex on its own (Melvin Vivas on X · notes), Asking a Coder bot to install Codex (Melvin Vivas on X · notes), Sign in with ChatGPT: Setting Usage Limits for Each App (Melvin Vivas on X · notes), Codex Cloud Environments Must Be Saved & Published Before Use (Melvin Vivas on X · notes) and 240 more

Try this

• Try the Impeccable design skill with your coding agent (e.g. Codex) to improve generated UI.