MCP

Adding MCP Tools

• Create a new tool in packages/playwright/src/mcp/browser/tools/your-tool.ts
• Register the tool in packages/playwright/src/mcp/browser/tools.ts
• Add ToolCapability in packages/playwright/src/mcp/config.d.ts
• Place new tests in tests/mcp/mcp-<category>.spec.ts

Building

• Assume watch is running at all times, run lint to see type errors

Testing

• Run tests as npm run ctest-mcp <category>
• Do not run test –debug

CLI

Adding commands

• CLI commands are based on MCP tools. Implement the corresponding MCP tool as per Adding MCP Tools section above, if needed.
• Add new CLI category for tool if needed:
  • Add Category in packages/playwright/src/mcp/terminal/command.ts
  • Update doc generator packages/playwright/src/mcp/terminal/helpGenerator.ts
• Register command in packages/playwright/src/mcp/terminal/commands.ts
• Update skill file at packages/playwright/src/skill/SKILL.md and references if necessary in packages/playwright/src/skill/references/
• Place new tests in tests/mcp/cli-<category>.spec.ts

Adding CLI options or Config options

When you need to add something to config.

• packages/playwright/src/mcp/program.ts
  • add CLI option and doc
• packages/playwright/src/mcp/config.d.ts
  • add and document the option
• packages/playwright/src/mcp/config.ts
  • modify FullConfig if needed
  • and CLIOptions if needed
  • add it to configFromEnv

Building

• Assume watch is running at all times, run lint to see type errors

Testing

• Run tests as npm run ctest-mcp cli-<category>
• Do not run test –debug

Lint

• run npm run flint to lint everything before commit

SKILL File

The skill file is located at packages/playwright/src/skill/SKILL.md. It contains documentation for all available CLI commands and MCP tools. Update it whenever you add new commands or tools. At any point in time you can run “npm run playwright-cli — –help” to see the latest available commands and use them to update the skill file.