Implementation:Microsoft Playwright Protocol Metainfo

Knowledge Sources	Microsoft_Playwright
Domains	Protocol, Tracing
Last Updated	2026-02-12 00:00 GMT

Overview

Auto-generated metadata map that associates every Playwright protocol method with display titles, visibility flags, and behavioral annotations used for tracing and debugging.

Description

This file (~326 lines) is generated by generate_channels.js and exports a single Map that maps protocol method names to their metadata. Each entry provides display and behavioral information used by Playwright's tracing, UI inspection, and debugging infrastructure.

export const methodMetainfo = new Map<string, {
  internal?: boolean,
  title?: string,
  slowMo?: boolean,
  snapshot?: boolean,
  pausesBeforeInput?: boolean,
  pausesBeforeAction?: boolean,
  group?: string
}>([...]);

Metadata Fields

• internal: When true, the method is hidden from trace viewers and user-facing logs (e.g., Root.initialize, LocalUtils.zip)
• title: Human-readable description shown in trace viewers, supports template variables (e.g., '{method} "{url}"', 'Wait for event "{info.event}"')
• slowMo: When true, the method respects the slowMo launch option for pacing
• snapshot: When true, a page snapshot is captured before/after the method for trace recording
• pausesBeforeInput: When true, the method pauses in debug mode before input actions
• pausesBeforeAction: When true, the method pauses in debug mode before the action executes
• group: Categorization string (e.g., 'getter', 'configuration') for grouping in trace viewers

Coverage

The map covers all protocol domains:

• APIRequestContext: fetch, storageState
• BrowserType: launch, launchPersistentContext, connectOverCDP
• Browser: close, newContext, newBrowserCDPSession
• BrowserContext: Cookie management, permissions, init scripts, page creation, tracing
• Page: Navigation, clicks, fills, screenshots, evaluation, file uploads, routing
• Frame: Same action set as Page, scoped to frames
• ElementHandle: Element-specific actions (click, fill, check, screenshot)
• Locator support: Wait for event info across Page, BrowserContext, Worker, WebSocket
• Android/Electron: Device-specific actions for mobile and desktop app testing
• PageAgent: AI agent methods (perform, expect, extract)

Usage

This metadata map is consumed by Playwright's tracing system, the Trace Viewer UI, and the debug/inspector mode to determine how to display protocol calls, whether to capture snapshots, and whether to pause for user inspection.

Code Reference

Source Location

• Repository: Microsoft_Playwright
• File: packages/playwright-core/src/utils/isomorphic/protocolMetainfo.ts

Import

import { methodMetainfo } from '../utils/isomorphic/protocolMetainfo';

Generation

# This file is auto-generated; do not edit manually
# Generated by: generate_channels.js

Related Pages

• Environment:Microsoft_Playwright_Node_Runtime_Environment