QA + a11y scanner: walks your running app's real user flows and reports what's broken.
io.github.Aboudjem/sniff MCP Server
The io.github.Aboudjem/sniff MCP server is described as a QA + accessibility scanner. It “walks your running app's real user flows” and reports what is broken, using scanning focused on accessibility and related quality checks.
🛠️ Key Features
QA and accessibility scanning via real user flow execution
sniff walking a buggy app and streaming findings with severity, confidence, steps to reproduce, and a fix
bash
claude plugin marketplace add Aboudjem/10x
claude plugin install sniff@10x
What it does
Most linters read your source without ever running your app, and end-to-end frameworks ask you to
write and maintain the tests yourself. sniff opens your running app in a real browser, clicks and
fills things like a user would, and judges what actually happened.
It finds 12 classes of bugs, from HTTP 500 routes and dead links to placeholder data, dead
submit buttons, forms wiped by the back button, stuck spinners, and mobile overflow.
It proves every one. Every finding carries the route and the ordered steps that produced it,
plus the screenshot and the console or network excerpt the check captured. No steps, no finding.
It has been measured. On a fixture app planted with 21 bugs across all 12 classes, plus a
clean control page, sniff finds 21 of 21 and reports nothing on the control page.
Install
The block above is the Claude Code path, through the 10x marketplace.
For any other agent, the Vercel skills CLI installs the same three skills:
bash
npx skills add Aboudjem/sniff
To use it as a plain command line tool, with no editor involved:
bash
npx sniff-qa --url http://localhost:3000
The npm package is sniff-qa and the binary it installs is sniff. Do not run npx sniff, which
is an unrelated package.
Node version, project install, and CI
Node.js 22 or newer. npm install -D sniff-qa adds it to a project's devDependencies, and
npx sniff-qa ci writes a GitHub Actions workflow with browser caching and report artifacts.
Use it
1. Start your app, with whatever dev server your project already uses.
bash
npm run dev
2. Walk it, from a second terminal. sniff auto-detects a dev server on the common ports, so
--url is optional, but passing it takes the guesswork out.
bash
npx sniff-qa --url http://localhost:3000
3. Read the findings. They print grouped by severity. Below is an abridged real run against this
repo's own planted-bug fixture, from npx sniff-qa --url http://localhost:4321 --ci --max-pages 12:
text
sniff v0.8.0 walking http://localhost:4321
26 findings (+1 low-confidence hidden; use --all)
CRITICAL (1)
• [confirmed] Page returns HTTP 500
/crash (route/broken-page)
- Navigate to /crash
- Server responded with HTTP 500
fix: The route throws server-side. Check the server logs/handler for this path and return a valid page or a proper error page.
shot: sniff-reports/crawl/_crash-desktop.png
✓ Scan complete: 26 issue(s) found. Exit code 1 so CI fails on bugs; pass --fail-on none to always exit 0.
Add --report for a self-contained HTML page you can send to someone. Run npx sniff-qa doctor if
the environment looks wrong.
What you get
A terminal report grouped by severity, each finding with steps, a fix, and a screenshot path.
A shareable file, a self-contained HTML report with --report or JSON with --json.
An exit code, non-zero when findings reach the --fail-on severity, so CI fails on real bugs.
A confidence label on each. uncertain is hidden from the terminal unless you pass --all.
New in 0.8.0:
--caps scan,report narrows the MCP server to the source scan and the saved-results reader, with
no browser launch and no browser download.
--storage-state auth.json walks a logged-in app. Cookie and token values from that file are
redacted from the text of every written report, though not from screenshot pixels.
An assert block in sniff.config caps findings by severity (maxCritical, maxHigh,
maxTotal), enforced on the command line by the walk, the source scan, and discovery.
Works in your editor
Works in Claude Code, Cursor, Codex, Copilot, Gemini CLI, and 70+ other agents through
npx skills add. The skills are Markdown, so they run on whatever model your editor points at.
Cursor, VS Code, Gemini CLI, Windsurf, Continue, OpenCode, and Zed take the same command as a JSON
or TOML entry. Every per-editor snippet is in docs/editors.md.
Good to know
IMPORTANT
No API key, no account, no signup, and no AI provider unless you set one up yourself. Walking and
scanning never edit your source. sniff fix is the only command that rewrites code, and only when
you run it.
NOTE
A walk clicks buttons and submits real forms, so it can create real data. Point it at a dev or
staging app, not at production. The first walk also downloads a Chromium build and caches it, so
that one run needs internet access.
It wants a running app. With no dev server up it falls back to a source-only scan and tells
you how to start the real walk. npx sniff-qa scan runs that scan on purpose.
Dead-link checking follows external links, so a walk makes requests to the third-party URLs
your own pages already link to.
A walk that finds bugs exits 1 on purpose, so CI fails the build. That is not a crash.
--fail-on none turns off the severity gate, though an assert budget can still fail the run.
Learn more
docs/editors.md, install and MCP snippets for every supported agent
