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

• uxc is installed and available in PATH.
• npx is available in PATH (Node.js installed).
• Network access for first-time @playwright/mcp package 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-cli as default command path.
• playwright-mcp-cli ... is equivalent to uxc "npx -y @playwright/mcp@latest --headless --isolated" ....
• Use direct uxc "" ... only as temporary fallback when link setup is unavailable.
• If browser profile conflict appears, keep --isolated in 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_snapshot over screenshots for model-action loops.

References

• Invocation patterns:

- references/usage-patterns.md