Testing Skills for AI Agents: Browser Flows and Headless Tests

Last updated: 2026-10-29

A useful test checks an expected behavior and makes the result observable. A browser interaction, a screenshot and a headless test suite can all help, but they answer different questions. These three Skills focus on software testing; choose the one that fits the application and evidence you need.

Choose a testing workflow

Web App Testing: inspect and exercise a local app

Web App Testing is Anthropic's Playwright-based workflow for checking local web applications. Its instructions cover inspecting the rendered page, identifying selectors, performing interactions and capturing screenshots or browser logs. A bundled helper can start and stop one or more servers.

Use it for a concrete frontend flow: state the starting URL, action and expected result. Python Playwright and its browser dependencies need to be available. A screenshot records a visual state; it should accompany an assertion or observation that explains what was checked.

Happy Browser Testing: work through a real browser

Happy Browser Testing uses the agent-browser CLI. Its entrypoint describes opening a page, taking an interactive snapshot, acting on the resulting element references and taking a fresh snapshot after the page changes.

Choose it for a browser interaction you want the agent to inspect step by step. Provide the expected outcome and a suitable test environment. The Skill depends on the CLI; an element reference from an earlier page state should not be treated as valid after navigation or a significant interface change.

Godot GDScript Headless Tests: run a suite without the editor

Godot GDScript Headless Tests addresses a different testing surface: GDScript logic in Godot projects. Its instructions describe a SceneTree runner, explicit failure counts and a nonzero process exit code for CI.

Use it when the project needs a headless test runner or a CI job that can detect failure. The workflow targets Godot 4.7, calls for importing a fresh checkout before tests and recommends timeouts for tests that wait on signals. Check the runner's exit code and output; a process that starts successfully has not necessarily verified the desired behavior.

Write the test brief

Name the behavior, starting conditions, actions and expected result. Specify the environment and any test data or accounts needed. Ask the agent to report what actually ran, what passed or failed, and what it could not verify. Screenshots and logs help explain a result, while assertions and exit codes make the intended outcome checkable.

These entries address functional testing. For security audits and authorized penetration testing, see Security Skills.