Install to Claude Code
npx -y skills add https://github.com/everyinc/compound-engineering-plugin --skill ce-test-browserDescription
ce test browser
SKILL.md
---
name: ce-test-browser
description: Run browser tests for pages affected by the current branch or PR.
argument-hint: "[PR number, branch name, 'current', or --port PORT]"
---
# Browser Test Skill
Run end-to-end browser tests on pages affected by a PR or branch changes using the `agent-browser` CLI.
## Modes
- **Manual (default):** the user controls the dev server. Follow the steps below as written, including the headed/headless question.
- **Pipeline (`mode:pipeline`):** invoked by LFG or another automated runner. The run is unattended — never block on a question. Read `references/pipeline-orchestration.md` from this skill's directory and follow it; it overrides the free-port scan (step 4), dev-server startup (step 5), and the headed/headless question (step 6). It still uses the preferred port that step 4 computes.
## Use `agent-browser` Only
Use the `agent-browser` CLI for every browser action in this skill — opening pages, clicking, filling forms, snapshots, screenshots — and use it exclusively. Do not use any other browser-automation tool, including a browser MCP integration, a built-in browser-control tool, Playwright, or Puppeteer. If the host offers several ways to drive a browser, always choose `agent-browser`.
- Claude Code: do not use Chrome MCP tools (`mcp__claude-in-chrome__*`).
- Codex: do not substitute unrelated browsing tools.
## Workflow
### 1. Verify `agent-browser` Is Installed
```bash
command -v agent-browser >/dev/null 2>&1 && echo "Ready" || echo "NOT INSTALLED"
```
If not installed, tell the user: "`agent-browser` is not installed. Run `/ce-setup` for the current install command, then install agent-browser and retry." Then stop — this skill cannot function without it.
This also requires a git repository with changes to test.
### 2. Determine Test Scope
**If PR number provided:**
```bash
gh pr view [number] --json files -q '.files[].path'
```
**If 'current' or empty:**
```bash
git diff --name-only main...HEAD
```
**If branch name provided:**
```bash
git diff --name-only main...[branch]
```
### 3. Map Changed Files to Routes
Map each changed file to the route(s) that render it, then build the list of URLs to test. The table below is a starting point of common patterns, not an exhaustive rule set — apply judgment for the project's actual layout:
| File Pattern | Route(s) |
|-------------|----------|
| `app/views/users/*` | `/users`, `/users/:id`, `/users/new` |
| `app/controllers/settings_controller.rb` | `/settings` |
| `app/javascript/controllers/*_controller.js` | Pages using that Stimulus controller |
| `app/components/*_component.rb` | Pages rendering that component |
| `app/views/layouts/*` | All pages (test homepage at minimum) |
| `app/assets/stylesheets/*` | Visual regression on key pages |
| `app/helpers/*_helper.rb` | Pages using that helper |
| `src/app/*` (Next.js) | Corresponding routes |
| `src/components/*` | Pages using those components |
### 4. Determine the Dev Server Port
Determine the preferred port using this priority:
1. **Explicit argument** — if the user passed `--port 5000`, use that directly.
2. **In-context project instructions** — if your active project instructions already in context explicitly state the dev-server port, use it. Don't grep instruction files for a port: prose mentions (docs, examples, troubleshooting) are unreliable and false-positive-prone — config files and `.env` are the trustworthy sources.
3. **package.json** — check dev/start scripts for `--port` flags.
4. **Environment files** — check `.env`, `.env.local`, `.env.development` for `PORT=`.
5. **Default** — fall back to `3000`.
```bash
# If your in-context project instructions state the dev-server port, set EXPLICIT_PORT first.
PORT="${EXPLICIT_PORT:-}"
if [ -z "$PORT" ]; then
PORT=$(grep -Eo '\-\-port[= ]+[0-9]{4,5}' package.json 2>/dev/null | grep -Eo '[0-9]{4,5}' | head -1)
fi
if [ -z "$PORT" ]; then
PORT=$(grep -h '^PORT=' .env .env.local .env.development 2>/dev/null | tail -1 | cut -d= -f2)
fi
PORT="${PORT:-3000}"
echo "Preferred dev server port: $PORT"
```
Manual mode uses this preferred port as-is — the user controls their own server, so do not scan for alternatives. In pipeline mode, `references/pipeline-orchestration.md` takes the preferred port value printed here and scans upward to a genuinely free port.
### 5. Verify the Dev Server Is Running
Confirm the server is up before asking the headed/headless question — a manual run with no server stops here, so asking first would waste the question.
```bash
if lsof -i ":${PORT}" -sTCP:LISTEN -t >/dev/null 2>&1; then
echo "Server running on port ${PORT}"
else
echo "Server not running on port ${PORT}"
echo "Start your dev server, then re-run:"
echo " Rails: bin/dev or rails server -p ${PORT}"
echo " Node/Next.js: npm run dev"
echo " Custom port: run this skill again with --port <your-port>"
exit 0
fi
```
In pipeline mode, do not stop here — `references/pipeline-orchestration.md` auto-starts the server in the background instead.
### 6. Choose Headed or Headless
Manual mode only — in pipeline mode, skip this step (see Modes; it defaults to headless).
Ask the user whether to run headed or headless using the platform's blocking question tool: `AskUserQuestion` in Claude Code (call `ToolSearch` with `select:AskUserQuestion` first if its schema isn't loaded), `request_user_input` in Codex, `ask_question` in Antigravity CLI (`agy`), `ask_user` in Pi (requires the `pi-ask-user` extension). Fall back to presenting options in chat only when no blocking tool exists in the harness or the call errors (e.g., Codex edit modes) — not because a schema load is required. Never silently skip the question:
```
Do you want to watch the browser tests run?
1. Headed (watch) - Opens visible browser window so you can see tests run
2. Headless (faster) - Runs in background, faster but invisible
```
Store the choice and use the `--headed` flag when the user selects option 1. Then confirm the server serves the root before iterating (add `--headed` if the user chose headed):
```bash
agent-browser open http://localhost:${PORT}
agent-browser snapshot -i
```
### 7. Test Each Affected Page
For each affected route:
**Navigate and capture snapshot:**
```bash
agent-browser open "http://localhost:${PORT}/[route]"
agent-browser snapshot -i
```
**For headed mode:**
```bash
agent-browser --headed open "http://localhost:${PORT}/[route]"
agent-browser --headed snapshot -i
```
**Verify key elements:**
- Use `agent-browser snapshot -i` to get interactive elements with refs
- Page title/heading present
- Primary content rendered
- No error messages visible
- Forms have expected fields
**Test critical interactions:**
```bash
agent-browser click @e1
agent-browser snapshot -i
```
**Take screenshots:**
```bash
agent-browser screenshot page-name.png
agent-browser screenshot --full page-name-full.png
```
### 8. Human Verification (When Required)
Pause for human input when testing touches flows that require external interaction. **Pipeline mode:** do not pause — log each such flow as Skip with the reason and continue.
| Flow Type | What to Ask |
|-----------|-------------|
| OAuth | "Please sign in with [provider] and confirm it works" |
| Email | "Check your inbox for the test email and confirm receipt" |
| Payments | "Complete a test purchase in sandbox mode" |
| SMS | "Verify you received the SMS code" |
| External APIs | "Confirm the [service] integration is working" |
Ask the user (using the platform's question tool, or present numbered options and wait):
```
Human Verification Needed
This test touches [flow type]. Please:
1. [Action to take]
2. [What to verify]
Did it work correctly?
1. Yes - continue testing
2. No - describe the issue
```
### 9. Handle Failures
When a test fails (**pipeline mode:** do not ask how to proceed — capture the error screenshot and repro steps, log the failure, and continue):
1. **Document the failure:**
- Screenshot the error state: `agent-browser screenshot error.png`
- Note the exact reproduction steps
2. **Ask the user how to proceed:**
```
Test Failed: [route]
Issue: [description]
Console errors: [if any]
How to proceed?
1. Fix now - debug and fix the failing test
2. Skip - continue testing other pages
```
3. **If "Fix now":** investigate, propose a fix, apply, re-run the failing test
4. **If "Skip":** log as skipped, continue
### 10. Test Summary
After all tests complete, present a summary:
```markdown
## Browser Test Results
**Test Scope:** PR #[number] / [branch name]
**Server:** http://localhost:${PORT}
### Pages Tested: [count]
| Route | Status | Notes |
|-------|--------|-------|
| `/users` | Pass | |
| `/settings` | Pass | |
| `/dashboard` | Fail | Console error: [msg] |
| `/checkout` | Skip | Requires payment credentials |
### Console Errors: [count]
- [List any errors found]
### Human Verifications: [count]
- OAuth flow: Confirmed
- Email delivery: Confirmed
### Failures: [count]
- `/dashboard` - [issue description]
### Result: [PASS / FAIL / PARTIAL]
```
## Quick Usage Examples
```bash
# Test current branch changes (auto-detects port)
/ce-test-browser
# Test specific PR
/ce-test-browser 847
# Test specific branch
/ce-test-browser feature/new-dashboard
# Test on a specific port
/ce-test-browser --port 5000
```
## agent-browser CLI Reference
Run `agent-browser --help` for all commands.
Key commands:
```bash
# Navigation
agent-browser open <url> # Navigate to URL
agent-browser back # Go back
agent-browser close # Close browser
# Snapshots (get element refs)
agent-browser snapshot -i # Interactive elements with refs (@e1, @e2, etc.)
agent-browser snapshot -i --json # JSON output
# Interactions (use refs from snapshot)
agent-browser click @e1 # Click element
agent-browser fill @e1 "text" # Fill input
agent-browser type @e1 "text" # Type without clearing
agent-browser press Enter # Press key
# Screenshots
agent-browser screenshot out.png # Viewport screenshot
agent-browser screenshot --full out.png # Full page screenshot
# Headed mode (visible browser)
agent-browser --headed open <url> # Open with visible browser
agent-browser --headed click @e1 # Click in visible browser
# Wait
agent-browser wait @e1 # Wait for element
agent-browser wait 2000 # Wait milliseconds
```
