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/AGENTS.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/agents-md)<a href="https://agentmods.dev/instructions/pbakaus/impeccable/agents-md"><img src="https://agentmods.dev/badge/instructions/pbakaus/impeccable/agents-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/agents-md"><img src="https://agentmods.dev/badge/instructions/pbakaus/impeccable/agents-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 | $0.04260 | $0.04260 |
| Opus 5.5 | $0.01704 | $0.01704 |
| Sonnet 5.5 | $0.00852 | $0.00852 |
| Haiku 4.5 | $0.00426 | $0.00426 |
Grade A, and why
impeccable AGENTS.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 — 112 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Repository Guidelines
Project Structure & Module Organization
skill/ is the source of truth for the Impeccable skill: SKILL.src.md, reference/, scripts/, and agents/. skill/scripts/ holds the launcher (impeccable, impeccable.cmd), the pinned engine VERSION, command-metadata.json, and the in-page live-mode JS. Every skill verb ({{scripts_path}}/impeccable <verb>) runs in the engine binary, built from this repo's Cargo workspace under crates/; the root ENGINE_VERSION pins the released binary used by installs. Read docs/ENGINE.md before changing runtime code. Build logic lives in scripts/, with provider configs in scripts/lib/transformers/. cli/ is the npm shim that runs the same binary, the browser extension lives in extension/, and regression coverage lives in the Rust crates and tests/, including fixtures under tests/fixtures/ and behavior goldens under tests/oracle/. The website and service live in the separate private impeccable-site repo. dist/ and build/ are generated and gitignored. The root harness folders (.agents/, .claude/, .cursor/, etc.) and plugin/ are generated distribution artifacts that are tracked for direct repo installs, not hand-authored source.
Build, Test, and Development Commands
cargo build --release -p impeccable- build this checkout's runtime intotarget/release/impeccable. This one binary is also the detector (impeccable detect); there is no separate detector binary. PointIMPECCABLE_BINat it.cargo test --workspace- run the Rust workspace tests.bun run test:rust-changed- run the Rust tests of the crates your change touches (against the merge base withorigin/main, working tree included) plus every crate that depends on them;--printshows the selection,--base <ref>changes the base. Full log intarget/test-rust-changed.log, one summary line on stdout.bun run build- source-first build: regeneratedist/, derived site assets, and validation output without syncing tracked harness folders.bun run build:release- release/distribution build: run the full build and sync tracked root harness folders plusplugin/.bun run rebuild- clean and rebuild everything from scratch without syncing tracked harness folders.bun run rebuild:release- clean and rebuild everything, including tracked harness output sync.bun test tests/build.test.js- run a focused Bun test.bun run fetch:engine- download the pinned engine binary for this machine intoskill/scripts/bin/<os>-<arch>/(or setIMPECCABLE_BINto a local build). The oracle and framework suites skip without it.bun run test- run the full Bun + Node test suite (includes the oracle replay against the engine binary and the plugin loader E2E, which installs the committedplugin/subtree into a sandboxed real Claude Code and skips cleanly when theclaudeCLI is absent).bun run test:live-e2e- opt-in live-mode E2E against framework fixtures (~2 min; needsnpx playwright install chromiumonce).bun run test:skill-behavior- opt-in LLM-backed checks that the SKILL.md Setup flow actually drives the agent (runs claude-sonnet-5 / gpt-5.6-luna / gemini-3.5-flash / deepseek-v4-flash; needs.envwith provider keys).bun run test:plugin-e2e- just the plugin loader E2E, for fast iteration onplugin/,skill/agents/, orscripts/build.jschanges.bun run build:extension- rebuild the extension bundle (it runscargo xtask bundle, which also refreshes the in-page detector bundle).
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 · +22 lines · +824 tokens per session 0db71f8c5a86
- 1mo ago Changed · +7 tokens per session f38d1d833b77
- 1mo ago Changed · -2 lines · +2 tokens per session 25ab093169c0
- 1mo ago First seen · 92 lines · 3,427 tokens per session scan A 19284fbc22ae
impeccable AGENTS.md is an instructions file published in the GitHub repository pbakaus/impeccable (81,612 stars, last pushed today), licensed Apache-2.0. It adds 4,260 tokens to every session, about $0.0170 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).