# Whitebox E2e

> Standardized guide and protocol for authoring robust Whitebox End-to-End tests using the Neural Link Playwright fixture. CRITICAL: Neo.mjs uses Playwright in a highly custom way. Standard Playwright patterns will fail. Triggers: Use this skill before writing, modifying, or executing Playwright End-to-End tests, or if the user asks you to write an E2E test, add end-to-end coverage, or test a component holistically.

- Skill: `neomjs/whitebox-e2e` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add neomjs/whitebox-e2e`
- Raw SKILL.md: https://api.skillmd.com/api/skills/neomjs/whitebox-e2e/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Web & Frontend
- Author: neomjs (https://skillmd.com/u/neomjs)
- Updated: 2026-09-21
- Page: https://skillmd.com/skills/neomjs/whitebox-e2e

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# Whitebox E2E Testing Protocol

If you are tasked with writing new End-to-End tests for Neo.mjs applications, you MUST immediately use the `view_file` tool to read and strictly adhere to `.agents/skills/whitebox-e2e/references/whitebox-e2e-protocol.md` before planning your assertions or writing any test code.

This prevents the creation of brittle, visual-only DOM locator tests by ensuring you utilize the deep-state introspection capabilities of the Neural Link fixture.