Browser Discovery Skill
Detect and use browser automation tools for documentation discovery when static fetching fails.
Variables
| Variable | Default | Description |
|---|---|---|
| PREFERRED_TOOL | auto | auto, antigravity, cursor, playwright |
| WAIT_TIMEOUT | 3 | Seconds to wait for JS rendering |
| MAX_PAGES | 50 | Maximum pages to discover per site |
Instructions
MANDATORY - Follow the Workflow steps below when browser automation is needed.
- •Always try curl first unless
js_required: trueis set - •Detect available browser tools before attempting automation
- •Prefer accessibility snapshots over screenshots for link extraction
Quick Decision Tree
code
Do you need browser automation? │ ├─ Curl returns full content? ──────────► NO - Use curl (docs-fetch-url) │ ├─ Curl returns <1KB or 403? ───────────► YES - Continue below │ Which browser tool to use? │ ├─ browser_subagent available? ─────────► antigravity-browser.md │ ├─ In Cursor IDE? ──────────────────────► cursor-browser.md │ ├─ Chrome debugging on :9222? ──────────► playwright-browser.md (wrapper) │ └─ No browser tool? ────────────────────► See "No Browser Available" section
Red Flags - STOP and Reconsider
If you're about to:
- •Use browser automation when curl would work
- •Skip tool detection and assume a specific tool exists
- •Take screenshots when snapshot would provide structured data
- •Navigate without waiting for JS rendering
STOP -> Check the appropriate cookbook -> Then proceed
Workflow
- • CHECKPOINT: Verify browser automation is actually needed
- •Curl response < 1KB?
- •Curl gets 403 Forbidden?
- •
js_required: truein config?
- • Detect available browser tools (priority order)
- • Select best available tool
- • CHECKPOINT: Read the cookbook for selected tool
- • Execute browser-based discovery
- • Parse results and return structured data
Tool Detection Priority
| Priority | Tool | Detection | Best For |
|---|---|---|---|
| 1 | Antigravity browser_subagent | Tool in tool list | Zero-config native |
| 2 | Cursor MCP (in-IDE) | mcp__cursor__browser_* | In Cursor IDE |
| 3 | Cursor CLI | which cursor-agent | Delegation from CLI |
| 4 | Playwright (wrapper) | curl localhost:9222/json/version | Full automation |
Cookbook
Antigravity Browser
- •IF:
browser_subagenttool available - •THEN: Read
cookbook/antigravity-browser.md
Cursor Browser
- •IF: In Cursor IDE or
cursor-agentavailable - •THEN: Read
cookbook/cursor-browser.md
Playwright Browser
- •IF: Chrome debugging accessible at localhost:9222
- •THEN: Read
cookbook/playwright-browser.md
When Browser Is Needed
Signs that a site requires browser automation:
- •Curl response < 1KB (JS-rendered content)
- •Response contains "please enable javascript"
- •Framework markers:
__NEXT_DATA__,window.__remixContext,window.__NUXT__ - •Only CSS/font resources returned (no text content)
No Browser Available
If no browser tool is detected:
code
No browser automation tool detected. Setup options: 1. Antigravity IDE: Built-in (zero config) 2. Cursor: cursor-agent available when installed 3. Claude Code: Launch Chrome with debugging: google-chrome --remote-debugging-port=9222 Then use the Playwright wrapper: python3 .claude/ai-dev-kit/dev-tools/mcp/wrappers/playwright_wrapper.py navigate "https://..."
Output
Return discovered pages as structured data:
json
{
"pages": [
{"url": "...", "title": "...", "section": "..."}
],
"nav_structure": "sidebar | tabs | accordion",
"js_required": true
}