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.
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SKILL.md
webapp-testing.SKILL.md
---name: webapp-testing
description: 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.
license: Complete terms in LICENSE.txt
---# Web Application Testing
To test local web applications, write native Python Playwright scripts.
**Helper Scripts Available**:
- `scripts/with_server.py` - Manages server lifecycle (supports multiple servers)
**Always run scripts with `--help` first** to see usage. DO NOT read the source until you try running the script first and find that a customized solution is abslutely necessary. These scripts can be very large and thus pollute your context window. They exist to be called directly as black-box scripts rather than ingested into your context window.
## Decision Tree: Choosing Your Approach
```
User task → Is it static HTML?
├─ Yes → Read HTML file directly to identify selectors
│ ├─ Success → Write Playwright script using selectors
│ └─ Fails/Incomplete → Treat as dynamic (below)
│
└─ No (dynamic webapp) → Is the server already running?
├─ No → Run: python scripts/with_server.py --help
│ Then use the helper + write simplified Playwright script
│
└─ Yes → Reconnaissance-then-action:
❌ **Don't** inspect the DOM before waiting for `networkidle` on dynamic apps
✅ **Do** wait for `page.wait_for_load_state('networkidle')` before inspection
## Best Practices
- **Use bundled scripts as black boxes** - To accomplish a task, consider whether one of the scripts available in `scripts/` can help. These scripts handle common, complex workflows reliably without cluttering the context window. Use `--help` to see usage, then invoke directly.
- Use `sync_playwright()` for synchronous scripts
- Always close the browser when done
- Use descriptive selectors: `text=`, `role=`, CSS selectors, or IDs
- Add appropriate waits: `page.wait_for_selector()` or `page.wait_for_timeout()`
## Reference Files
- **examples/** - Examples showing common patterns:
- `element_discovery.py` - Discovering buttons, links, and inputs on a page
- `static_html_automation.py` - Using file:// URLs for local HTML
- `console_logging.py` - Capturing console logs during automation
