Playwright CLI Skill

Environment Variables

This skill requires the following environment variables:

• SKILLS_ROOT - Path to the skills directory (automatically set by the system)
• LOBSTERAI_SKILLS_ROOT - Alternative skills root path (optional, defaults to SKILLS_ROOT)

Prerequisites

• Node.js and npm must be installed
• npx command must be available
• Optional: @playwright/mcp package can be installed globally for direct CLI access

Drive a real browser from the terminal using playwright-cli. Prefer the bundled wrapper script so the CLI works even when it is not globally installed. Treat this skill as CLI-first automation. Do not pivot to @playwright/test unless the user explicitly asks for test files.

Prerequisite check (required)

Before proposing commands, check whether npx is available (the wrapper depends on it):

bash
command -v npx >/dev/null 2>&1

If it is not available, pause and ask the user to install Node.js/npm (which provides npx). Provide these steps verbatim:

bash
# Verify Node/npm are installed
node --version
npm --version

# If missing, install Node.js/npm, then:
npm install -g @playwright/mcp@latest
playwright-cli --help

Once npx is present, proceed with the wrapper script. A global install of playwright-cli is optional.

Skill path (set once)

bash
export SKILLS_ROOT="${LOBSTERAI_SKILLS_ROOT:-${SKILLS_ROOT:-$HOME/Library/Application Support/LobsterAI/SKILLs}}"
export PWCLI="$SKILLS_ROOT/playwright/scripts/playwright_cli.sh"

Installed skills resolve from $LOBSTERAI_SKILLS_ROOT / $SKILLS_ROOT (production default: app userData/SKILLs, macOS usually ~/Library/Application Support/LobsterAI/SKILLs).

Quick start

Use the wrapper script:

bash
"$PWCLI" open https://playwright.dev --headed
"$PWCLI" snapshot
"$PWCLI" click e15
"$PWCLI" type "Playwright"
"$PWCLI" press Enter
"$PWCLI" screenshot

If the user prefers a global install, this is also valid:

bash
npm install -g @playwright/mcp@latest
playwright-cli --help

Core workflow

1. Open the page.
2. Snapshot to get stable element refs.
3. Interact using refs from the latest snapshot.
4. Re-snapshot after navigation or significant DOM changes.
5. Capture artifacts (screenshot, pdf, traces) when useful.

Minimal loop:

bash
"$PWCLI" open https://example.com
"$PWCLI" snapshot
"$PWCLI" click e3
"$PWCLI" snapshot

When to snapshot again

Snapshot again after:

• navigation
• clicking elements that change the UI substantially
• opening/closing modals or menus
• tab switches

Refs can go stale. When a command fails due to a missing ref, snapshot again.

Recommended patterns

Form fill and submit

bash
"$PWCLI" open https://example.com/form
"$PWCLI" snapshot
"$PWCLI" fill e1 "user@example.com"
"$PWCLI" fill e2 "password123"
"$PWCLI" click e3
"$PWCLI" snapshot

Debug a UI flow with traces

bash
"$PWCLI" open https://example.com --headed
"$PWCLI" tracing-start
# ...interactions...
"$PWCLI" tracing-stop

Multi-tab work

bash
"$PWCLI" tab-new https://example.com
"$PWCLI" tab-list
"$PWCLI" tab-select 0
"$PWCLI" snapshot

Wrapper script

The wrapper script uses npx --package @playwright/mcp playwright-cli so the CLI can run without a global install:

bash
"$PWCLI" --help

Prefer the wrapper unless the repository already standardizes on a global install.

References

Open only what you need:

• CLI command reference: references/cli.md
• Practical workflows and troubleshooting: references/workflows.md

Guardrails

• Always snapshot before referencing element ids like e12.
• Re-snapshot when refs seem stale.
• Prefer explicit commands over eval and run-code unless needed.
• When you do not have a fresh snapshot, use placeholder refs like eX and say why; do not bypass refs with run-code.
• Use --headed when a visual check will help.
• When capturing artifacts in this repo, use output/playwright/ and avoid introducing new top-level artifact folders.
• Default to CLI commands and workflows, not Playwright test specs.