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Web app testing skill

Web app testing is part of Anthropic's skills repository. Its job is to drive a local web app with Playwright to check behavior, read logs and take screenshots. It loads on its own when a request matches its description, and you can also call it by name. It bundles Python scripts that the instructions call for.

Source

When the agent reaches for it

The agent keeps every installed skill's description in view and loads the full instructions when a request matches. This is the description it reads:

Toolkit for interacting with and testing local web applications using Playwright. Supports verifying frontend functionality, debugging UI behavior, capturing browser screenshots, and viewing browser logs.

What the instructions cover

The sections of its SKILL.md, in order.

  • Decision Tree: Choosing Your Approach
  • Example: Using withserver.py
  • Reconnaissance-Then-Action Pattern
  • Common Pitfall
  • Best Practices
  • Reference Files

What ships with it

Besides SKILL.md, the folder carries these. The agent opens them only when a step in the instructions calls for one.

  • examples/ 3 files · 3 KB
  • scripts/ 1 file · 4 KB

Install the web app testing skill

In Claude Code, run this in a session. It comes from the publisher's own instructions.

Claude Code 
/plugin marketplace add anthropics/skills
/plugin install example-skills@anthropic-agent-skills

License: Apache-2.0.

Questions people ask

How do I install the web app testing skill?

In Claude Code, run /plugin marketplace add anthropics/skills, then /plugin install example-skills@anthropic-agent-skills.

When does the agent use the web app testing skill?

When a request matches its description. The agent keeps only the name and description of each installed skill in view, and reads the full instructions when a task fits. You can also ask for it by name.

Start with one machine.

Add the others when the work needs them, and the cloud when it has to keep going without you.

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