Impeccable is a design-guidance toolkit for AI coding agents that helps them create and refine frontend interfaces. It is intended for developers using AI to build user interfaces, with commands, browser iteration, and rule-based design checks.
Borrowing it
Nothing to install: this file belongs to pbakaus/impeccable. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/pbakaus/impeccable/main/CLAUDE.mdgit clone --depth 1 https://github.com/pbakaus/impeccableWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/instructions/pbakaus/impeccable/claude-md)<a href="https://agentmods.dev/instructions/pbakaus/impeccable/claude-md"><img src="https://agentmods.dev/badge/instructions/pbakaus/impeccable/claude-md/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/instructions/pbakaus/impeccable/claude-md"><img src="https://agentmods.dev/badge/instructions/pbakaus/impeccable/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.13813 | $0.13813 |
| Opus 5.5 | $0.05525 | $0.05525 |
| Sonnet 5.5 | $0.02763 | $0.02763 |
| Haiku 4.5 | $0.01381 | $0.01381 |
Grade A, and why
impeccable CLAUDE.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured today.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 391 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Project Instructions for Claude
Architecture (v3.0+)
There is one user-invocable skill, impeccable, with 24 commands underneath it. Users type /impeccable polish, /impeccable audit, etc. The skill is defined in skill/:
SKILL.src.md— frontmatter (with the auto-trigger-optimized description and theallowed-toolslist), shared design laws, and the Commands router table. ProviderSKILL.mdfiles are generated from this source.reference/— one<command>.mdper command (audit.md,polish.md,critique.md, etc.), the shared playbooks the router loads outside the command table (new-work.md,craft-floor.md,operate.md,routing.md), and the native platform references (ios.md,android.md). When a sub-command is matched, the router loads its reference file.scripts/command-metadata.json— single source of truth for each command's description, argument hint, and (eventually) category. Both the build and the engine'spinverb read from this.scripts/impeccable(+impeccable.cmd,VERSION): the launcher every skill verb goes through. See Engine binary below.impeccable pin— an engine verb that creates/removes lightweight redirect shims so users can have/auditas a standalone shortcut that delegates to/impeccable audit.
Engine binary (the runtime behind every verb)
The skill has no runtime of its own. Every command the skill text runs is {{scripts_path}}/impeccable <verb> (Setup step 1 says impeccable context; impeccable.cmd is the Windows twin for shells without sh). skill/scripts/impeccable is a POSIX sh launcher: it execs $IMPECCABLE_BIN if set, else the sibling scripts/bin/<os>-<arch>/impeccable[.exe], else ~/.impeccable/bin/impeccable, else the version-pinned user cache ~/.impeccable/bin/<VERSION>/, else impeccable on PATH, and as a last resort downloads the pinned version into that cache. It exports IMPECCABLE_SKILL_DIR (the skill dir, for reference/*.md and command-metadata.json) and IMPECCABLE_SELF (how the binary spells itself in the commands it prints).
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- today Changed · +4 lines · +211 tokens per session 69e79b65474c
- 3d ago Changed · +538 tokens per session 8507c6ce7f05
- 7d ago Changed · +2 lines · +333 tokens per session e4e2ec22a234
- 13d ago Changed · +1 lines · +158 tokens per session f488435a89c2
- 14d ago Changed · +2 lines · +156 tokens per session 64476417a320
- 1mo ago Changed 7de8f7ff4a16
- 1mo ago Changed · +15 lines · +2,181 tokens per session 05d187fcc06f
- 1mo ago Changed · +13 lines · +556 tokens per session d09d9116b9fb
- 1mo ago First seen · 354 lines · 9,680 tokens per session scan A 46f348a2ac42
impeccable CLAUDE.md is an instructions file published in the GitHub repository pbakaus/impeccable (81,612 stars, last pushed today), licensed Apache-2.0. It adds 13,813 tokens to every session, about $0.0553 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other instructions, from other repositories
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
next.js AGENTS.md
AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, cache eligibility and rollout and applying the notice (cutover).
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.
deepseek-harness AGENTS.md
AGENTS.md instructions for deepseek-ai/deepseek-harness, covering agents.md, pre-stable apis and released session data, repository layout, commands and host sandbox failures.
vscode copilot-instructions.md
Copilot instructions for microsoft/vscode, covering vs code copilot instructions, project overview, root folders, core architecture (src/ folder) and built-in extensions (extensions/ folder).