clerk-testing Skill for Claude: What It Does and How to Install It

Makes Claude set up Playwright or Cypress end-to-end tests for Clerk sign-in flows.

Installs: 47.2K; on skills.sh
Stars: 89; on GitHub
Updated: Oct 2026; last repo commit

This is Clerk's own testing skill. It is a short guide: it sends Claude to Clerk's Playwright or Cypress docs, then applies a few rules. Use development keys only, call setupClerkTestingToken() before auth pages, and save signed-in state with storageState for speed.

The folder holds only SKILL.md and bundles no scripts. It leans on Clerk's online docs, which Claude fetches with WebFetch.

Good for

Developers testing sign-in and sign-up flows built on Clerk
Teams who want fast tests that reuse a signed-in session
Playwright and Cypress users

Install clerk-testing

Claude Code

Copy this prompt.

Install the clerk-testing skill in Claude Code. Run this command:

/plugin marketplace add clerk/skills
/plugin install clerk@clerk-skills

Then check that it loaded and tell me how to use it.

2
Paste it into Claude Code. It shows the change and asks before running it.

Pick one route. The Clerk plugin installs all 20 skills in the repo plus the hosted Clerk MCP server (mcp.clerk.com/mcp) from its .mcp.json; the skills CLI routes install skills only. Per the README, the clerk plugin replaces the earlier clerk-skills@clerk Codex plugin and the earlier core, frameworks, features and mobile Copilot plugins, and Copilot may leave clerk@clerk-skills disabled until you run copilot plugin enable clerk@clerk-skills.

From the project README. Source.

What's in the skill

When it loads

E2E testing for Clerk apps. Use with Playwright or Cypress for auth flow tests.

Sections in SKILL.md

Decision Tree
Mental Model
Workflow
Best Practices
Anti-Patterns
Framework-Specific
See Also

Key facts

Author: Clerk (vendor's own repo)
Repo: clerk/skills
License: MIT (README, plugin.json and the SKILL.md frontmatter say MIT; the repo has no LICENSE file)
Installs on skills.sh: 47,172 (Nov 2, 2026)
GitHub stars: 89 for the whole repo (Nov 2, 2026)
Last repo commit: Oct 30, 2026
Audits on skills.sh: Gen Agent Trust Hub: pass, Socket: pass, Snyk: pass
What it includes: 1 file: SKILL.md. It bundles no scripts
Part of: Plugin clerk: 20 skills plus the Clerk MCP server
Needs: A publishable key and CLERK_SECRET_KEY or CLERK_TESTING_TOKEN

What it includes

Points to Clerk's testing overview, Playwright and Cypress guides
It tells Claude to WebFetch the right page and follow it.
Try: “Add Playwright tests for auth”
Network · Framework decision tree
Initializes the test environment
Write · clerkSetup()
Bypasses bot detection; call it before navigating to auth pages
Write · setupClerkTestingToken()
Saves signed-in state between tests so UI sign-in is not repeated
Write · storageState
Playwright uses globalSetup; Cypress adds addClerkCommands to the support file
Write · Playwright and Cypress setup
Use test keys, wait for [data-clerk-component], avoid production keys in tests
The anti-patterns table has 3 rows.
Best practices and anti-patterns

From the official docs

Permissions

Low risk

What it can do

Read your data
Create and change things
Delete things
Read-only mode

Watch out for

It edits your test setup
Claude adds global setup, testing-token calls and storageState files to your Playwright or Cypress project. Review the diff on a branch. github.com
It may create a Clerk app and keys
If the project has no keys, SKILL.md suggests `npx clerk@latest init`, which creates a Clerk application and writes development-instance keys to the env file. Tests should use pk_test and sk_test keys only. github.com
The Clerk plugin also adds an MCP server
The plugin bundles .mcp.json, which registers the hosted Clerk MCP server at mcp.clerk.com/mcp. plugin.json lists no hooks. The skills CLI and folder routes do not add it. github.com

Technical details

Turning on read-only	There is no read-only switch. Claude writes test code into your project.
Talks to	clerk.com
Sign-in and keys	Needs a publishable key and either CLERK_SECRET_KEY or CLERK_TESTING_TOKEN, per the compatibility field. SKILL.md says to use development-instance keys only.
Scopes	Writes Playwright or Cypress test setup in your project Fetches Clerk testing docs with WebFetch May run npx clerk@latest init to create development keys

Questions

What does the clerk-testing skill do?

It makes Claude set up end-to-end tests for Clerk sign-in flows with Playwright or Cypress. The skill is short. It points Claude to Clerk's own testing docs and adds rules such as using test keys and a testing token.

How do I install clerk-testing?

Use the install box above. The Clerk plugin installs all 20 skills. npx skills add clerk/skills installs the skills alone.

Which keys should tests use?

Development-instance keys only (pk_test_ and sk_test_). SKILL.md lists production keys in tests as a security risk.

What does setupClerkTestingToken do?

SKILL.md says it bypasses bot detection. Call it before you navigate to auth pages, or auth fails.

Do I need a Clerk account for tests?

Not necessarily. The compatibility note says clerk init can generate temporary development keys without an account. Tests need a publishable key plus CLERK_SECRET_KEY or CLERK_TESTING_TOKEN.

Is it safe?

It bundles no scripts. It edits your test setup, may run npx clerk@latest init if you have no keys, and fetches docs from clerk.com. Our advice: run tests against a development instance only.

Does it work in the Claude app?

The README documents Claude Code, Codex, Cursor, GitHub Copilot CLI and the skills CLI. It documents no Claude app upload route, so use one of those.

Is it an official Clerk skill?

It is in Clerk's own repo, and the repo's marketplace.json describes the plugin as "Official Clerk skills for AI coding agents".

Information

updated Nov 2, 2026

Repository: clerk/skills
Folder: skills/clerk-testing

clerk/skills skills.sh

Sources

Docs, issue trackers and discussions this page is built from.

Show all 5

clerk/skills README · github.com
clerk/skills marketplace.json · github.com
clerk plugin.json · github.com
clerk/skills .mcp.json · github.com
clerk-testing SKILL.md · github.com