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TestingDevToolsAutomationAI Agent Skill

browser-testing-with-devtools

Automated browser diagnostics for validating unexpected states, edge cases, and client-side performance.

addyosmani/agent-skills
22.3k stars
22.3k installs
Updated: 2026-05-14

Install Options

Install into Claude Code, Cursor, Codex, or Antigravity with:

$ npx skills add addyosmani/agent-skills@browser-testing-with-devtools

Real Work Situation Solved

Write acceptance criteria for an AI feature without missing edge cases

You've drafted acceptance criteria - but did you cover the cases where the AI answers wrong, ambiguous, or unsafe?

5-Step Action Framework

  1. 1Write each scenario as Given/When/Then, not general prose.
  2. 2Cover the "normal" happy path first, then the "boundary" cases (minimum/maximum input).
  3. 3Add an "ambiguous" scenario - when the input doesn't give the AI enough to answer confidently.
  4. 4Add an "unsafe" scenario - when the input deliberately probes for a vulnerability or asks for policy-violating content.
  5. 5For every scenario, spell out the expected behavior when the AI gets it wrong - not just when it gets it right.
Before

"The AI must answer the user's question correctly."

After

"Given a question outside the model's training data, When confidence is too low to answer, Then the AI must say 'I'm not sure' instead of guessing."

Related Course Lesson

AI Agents for PMLesson 17

Go to Lesson

SKILL.md Source Instructions

SKILL.md • Read-only preview
# Browser Testing Skill

Automate verification of interactive states, accessibility violations, and network edge-case behaviors.