Playwright MCP Skill
Use this skill to run Playwright MCP operations through uxc using fixed stdio endpoints.
Reuse the uxc skill for generic protocol discovery, auth/error handling, and envelope parsing rules.
Prerequisites
uxcis installed and available inPATH.npxis available inPATH(Node.js installed).- Network access for first-time
@playwright/mcppackage fetch. - Browser runtime can start locally (headless mode is default in this skill).
Core Workflow (Playwright-Specific)
Endpoint candidate inputs before finalizing:
- Raw package form from docs:
npx @playwright/mcp@latest - Reliable non-interactive form:
npx -y @playwright/mcp@latest - Isolated/headless stable form (default for this skill):
- npx -y @playwright/mcp@latest --headless --isolated - Shared-profile headless form (for persistent login state): - npx -y @playwright/mcp@latest --headless --user-data-dir ~/.uxc/playwright-profile - Shared-profile headed form (for interactive debug with same login state): - npx -y @playwright/mcp@latest --user-data-dir ~/.uxc/playwright-profile
- Verify protocol/path from official source and probe:
- Official source: https://github.com/microsoft/playwright-mcp - probe candidate endpoints with: - uxc "npx -y @playwright/mcp@latest --headless --isolated" -h - Confirm protocol is MCP stdio (protocol == "mcp" in envelope).
- Detect auth requirement explicitly:
- Run host help or a minimal read call and inspect envelope. - @playwright/mcp default flow is no OAuth/API key for local stdio use.
- Use fixed link command by default:
- command -v playwright-mcp-cli - If missing, create it: - uxc link playwright-mcp-cli "npx -y @playwright/mcp@latest --headless --isolated" - Optional shared-profile dual command setup for persistent sessions: - command -v playwright-mcp-headless - command -v playwright-mcp-ui - uxc link --daemon-exclusive ~/.uxc/playwright-profile playwright-mcp-headless "npx -y @playwright/mcp@latest --headless --user-data-dir ~/.uxc/playwright-profile" - uxc link --daemon-exclusive ~/.uxc/playwright-profile playwright-mcp-ui "npx -y @playwright/mcp@latest --user-data-dir ~/.uxc/playwright-profile" - playwright-mcp-cli -h - If command conflict is detected and cannot be safely reused, stop and ask skill maintainers to pick another fixed command name.
- Inspect operation schema before execution:
- playwright-mcp-cli browser_navigate -h - playwright-mcp-cli browser_snapshot -h - playwright-mcp-cli browser_click -h
- Prefer read-first interaction:
- Start with navigation/snapshot before mutating page state.
- Execute actions with explicit confirmation when impact is high:
- Confirm before form submission, checkout, delete/destructive actions, or irreversible multi-step flows.
Guardrails
- Keep automation on JSON output envelope; do not rely on
--text. - Parse stable fields first:
ok,kind,protocol,data,error. - Use
playwright-mcp-clias default command path. playwright-mcp-cli <operation>...is equivalent touxc "npx -y @playwright/mcp@latest --headless --isolated" <operation>....- Use direct
uxc "<endpoint>"...only as temporary fallback when link setup is unavailable. - If browser profile conflict appears, keep
--isolatedin endpoint and retry via the same fixed link command. - When using shared
--user-data-dir, run headless/headed links serially (not concurrently). - To enable seamless switching between headed UI login and headless CLI automation using the same profile directory, set a daemon exclusive key:
- Prefer link-level setup (recommended above), or set UXC_DAEMON_EXCLUSIVE=~/.uxc/playwright-profile for ad-hoc runs. - If the profile is still busy (another session is actively running), fallback: uxc daemon stop
- Prefer
browser_snapshotover screenshots for model-action loops.
References
- Invocation patterns:
- references/usage-patterns.md