Impeccable: a free design toolkit for Claude Code and Codex

Impeccable gives AI coding agents a vocabulary for design work. Instead of asking for a page to look better and leaving the meaning open, you can ask for a critique, a typography pass or a focused polish of an existing interface.

It is a free, open-source project, published under the Apache 2.0 license. You can explore it on the official website and inspect the source on GitHub. Free here refers to the toolkit; the coding agent or model you use with it may have separate usage charges.

This guide explains the documented workflow and what makes its approach useful. It is not a claim that we have benchmarked Impeccable against other design tools.

A design review and a finishing pass have different purposes. A review identifies what needs attention. A finishing pass works on details within an existing direction. Impeccable's command set makes that distinction easier to express.

The documentation includes critique for design assessment, audit for implementation concerns, typeset for typography, and polish for refinement. Other commands address layout, visual intensity and simplification.

The benefit is the shape of the request. If the offer is difficult to understand, adding motion is unlikely to solve the problem. If the direction is sound but spacing is inconsistent, replacing the whole layout may discard good work. A named task helps you ask for the kind of change you actually need.

Impeccable documents separate roles for PRODUCT.md and DESIGN.md. The first records who the product serves and what those people need. The second records the visual system the work should follow. Its init and document commands address those different records.

That separation is useful because a color choice and a product fact have different reasons for changing. A new palette should not rewrite the audience. A clearer account of the audience may change which information belongs first without requiring a different typeface.

Read those files after they are created. A durable record is useful only if it contains the decisions you intend to keep. The same principle applies when you write your own design skill: make its inputs and rules distinct before giving it a sequence of actions.

Impeccable's Live Mode is documented as a way to work with the running interface: select an area, explore a change and compare variations. This makes the visible result part of the workflow.

That is the part worth preserving in any AI design process. A description of a correction is not the correction itself. Open the result and check whether the text is easier to read, related controls belong together and the main action remains clear on a phone.

Keep the comparison bounded. Use the same content and viewport when judging a layout change. Otherwise, a shorter headline or a different image can make a version look better without showing whether the layout decision helped.

The GitHub repository lets you examine the instructions and implementation rather than treating the tool as an unexplained prompt. It is also a place to follow changes and report reproducible issues.

Impeccable documents a detector CLI alongside its agent-led design work. The distinction matters: a repeatable check for a known pattern is different from a judgment about whether a page communicates well. A clean check result can support a review without deciding the entire design.

If you are learning to write skills, study how responsibilities are separated. Look for the task a command accepts, the context it reads and the result it is meant to produce. Borrow the organizational lesson; follow the project's license when reusing its code.

The official getting-started guide uses npx impeccable install from your project folder, followed by a reload of the coding tool. It currently specifies Node.js 22.18 or later. Follow that guide for the current setup rather than assuming an older installation command still applies.

Command syntax depends on the client. The documentation uses /impeccable in its general examples and $impeccable in Codex. The Claude Code marketplace-plugin route uses a namespaced command. Choose the syntax for the installation you actually have.

Before running a design pass, write down the page, its main visitor action and the decisions that must remain. The downloadable brief below gives you a place to record them. It is a SiteSorted planning guide, not an Impeccable plugin or a copy of its source.

Impeccable is a useful option when you are directing design work inside a coding-agent workflow. Its focused commands and inspectable source give that work a practical structure.

SiteSorted is for founders who want to turn a product brief or visual reference into a launch-ready website. Our standard is visual fidelity: type, spacing, imagery and responsive behavior that fit the intended design. We want the finished site to look considered, with every part serving the page.

If you are already building in Claude Code or Codex, Impeccable is worth exploring. If your next task is to create the startup website itself, look at SiteSorted as well. In either case, judge the choice by the website you can inspect and use.