Browser CDP Inspect

Browser Rendering inspection beyond screenshots - navigate with @cloudflare/puppeteer and return title, cookies, document metadata, and performance timing.

API ReferenceCopy Anchor Link

GET /inspectCopy Anchor Link

url string (required)

http:// or https:// target.

Navigation timeout: 20s. Uses waitUntil: "domcontentloaded" to stay under the Worker request budget.

Example RequestCopy Anchor Link

curl "https://your-worker.workers.dev/inspect?url=https://example.com"

Success ResponseCopy Anchor Link

{
  "title": "Example Domain",
  "url": "https://example.com/",
  "cookiesCount": 0,
  "documentTitle": "Example Domain",
  "performance": { "domContentLoaded": 120.5 },
  "userAgent": "..."
}

Error CodesCopy Anchor Link

• 400 - Missing or non-http(s) url (INVALID_URL)
• 502 - Browser launch or navigation failure (INSPECT_ERROR)

Use CasesCopy Anchor Link

• Inspect rendered page metadata without capturing a screenshot
• Count cookies and read document title after JS load
• Collect basic performance timing from Puppeteer/CDP
• Debug SPA shells that need a real browser, not raw HTML fetch

LimitationsCopy Anchor Link

• Browser Rendering requires remote mode (wrangler dev --remote) or a deployed Worker
• 20s navigation timeout; domcontentloaded only (not full network idle)
• Returns a subset of CDP data - not a full DevTools dump
• Subject to Browser Rendering quotas and concurrency limits

Use in your projectCopy Anchor Link

import { ALLOWED_SCHEMES } from "../constants/defaults";export function validateUrl(input: string | undefined): string | null {  if (!input || typeof input !== "string") return null;  const trimmed = input.trim();  if (!trimmed) return null;  try {    const url = new URL(trimmed);    if (!ALLOWED_SCHEMES.includes(url.protocol as (typeof ALLOWED_SCHEMES)[number])) {      return null;    }    return url.href;  } catch {    return null;  }}

DeploymentCopy Anchor Link

curl "https://your-worker.workers.dev/inspect?url=https://www.cloudflare.com"

Local DevelopmentCopy Anchor Link

cd apps/experiments/browser-cdp-inspect
npm install
npm run dev

For Browser Rendering locally, prefer remote mode:

npx wrangler dev --remote

curl "http://localhost:8787/inspect?url=https://example.com"

ConfigurationCopy Anchor Link

wrangler.json declares:

• Browser binding BROWSER
• Compatibility flag nodejs_compat_v2

Cloudflare Features UsedCopy Anchor Link

• Workers - Edge compute runtime
• Browser Rendering - Headless browser at the edge
• @cloudflare/puppeteer - Puppeteer/CDP control