name: Browserless description: >- Vocabulary of key terms, concepts, objects, endpoints, and operations used across the Browserless cloud and open-source headless-browser platform. Covers BrowserQL (BQL), Browsers-as-a-Service (BaaS), the REST API family, session management, stealth, residential proxies, CAPTCHA solving, hybrid LiveURL automation, and the official Model Context Protocol server. version: '1.0' created: '2026-05-25' modified: '2026-05-25' tags: - Headless Browser - Browser Infrastructure - Web Automation - AI Agents - BrowserQL - MCP terms: - term: Browserless definition: >- The cloud service and the namesake open-source Docker image (browserless/browserless) that runs managed Chromium, Chrome, Edge, Firefox, and WebKit browsers as a service. category: Platform tags: - Platform - Core - term: BrowserQL (BQL) definition: >- A GraphQL automation language for driving browsers via mutations such as goto, click, type, evaluate, html, mapSelector, screenshot, pdf, and reconnect. Designed for stealth scraping of heavily-defended sites where Puppeteer or Playwright scripts get blocked. category: API Surface tags: - BrowserQL - GraphQL - Stealth - term: BaaS (Browsers-as-a-Service) definition: >- The WebSocket connection surface that lets existing Puppeteer (connect), Playwright (connectOverCDP / connect), and Selenium clients drive remote browsers running in Browserless infrastructure. category: API Surface tags: - BaaS - CDP - WebSocket - term: REST API definition: >- The HTTP/JSON endpoint family hung off /chrome, /chromium, and /edge prefixes — including /screenshot, /pdf, /content, /scrape, /function, /performance, /download, /export, /search, /smart-scrape, /map, /crawl, and /unblock — for one-shot browser operations without a browser library. category: API Surface tags: - REST - Endpoints - term: Regional Endpoint definition: >- A geographic host of the form production-{sfo,lon,ams}.browserless.io that selects which data center runs the browser. Affects latency, egress IP geography, and data residency. category: Endpoint tags: - Regions - Infrastructure - term: Token definition: >- The API token, passed as ?token=... on the connection URL (and accepted in headers for some surfaces), that authenticates all Browserless API calls and tracks billing. category: Concept tags: - Auth - Billing - term: Session definition: >- A live browser instance backed by a Chromium / Chrome / Edge / Firefox / WebKit process. Identified by an ID, managed via the /session and /sessions endpoints, and reusable across BQL queries and reconnects. category: Core Object tags: - Sessions - Core - term: Profile definition: >- A reusable, encrypted browser-profile object (cookies, localStorage, authenticated state) created and refreshed via /profile and /profile/refresh and attached at session creation time. category: Core Object tags: - Profiles - Persistence - term: Stealth Route definition: >- The /stealth/bql (BQL) and /stealth/* (BaaS) paths that apply hardened fingerprint mitigations, entropy injection, and WebGL randomization to reduce bot detection. category: Concept tags: - Stealth - Anti-Bot - term: Residential Proxy definition: >- A pool of residential IP addresses available to sessions via launch parameters or BQL, with country/city/sticky session selectors. Billed at 6 units per MB. category: Concept tags: - Proxy - Anti-Bot - term: CAPTCHA Solving definition: >- The built-in pipeline that detects and resolves reCAPTCHA, hCaptcha, DataDome, Lemin, MTCaptcha, and slider challenges. Billed at 10 units per successful solve. category: Concept tags: - CAPTCHA - Anti-Bot - term: Smart Scrape definition: >- The /smart-scrape REST endpoint that automatically chooses the cheapest strategy (HTTP fetch, proxy, headless browser, CAPTCHA solving) to retrieve and structure page content. category: Endpoint tags: - REST - AI - term: Crawl definition: >- The /crawl REST endpoint that performs depth-bounded, filterable site crawls and returns structured per-page results. Supports GET, POST, and DELETE. category: Endpoint tags: - REST - AI - term: Search definition: >- The /search REST endpoint that performs token-efficient web search from inside Browserless, aimed at AI/agent workloads. category: Endpoint tags: - REST - AI - term: LiveURL definition: >- The Browserless.liveURL CDP commands and embedded UI that hand control of a running session to a human (or watching agent) over a shareable browser URL, then return control to the script. Used in hybrid automation flows. category: Concept tags: - Hybrid - LiveURL - term: Reconnect definition: >- A BQL mutation (and REST /session pattern) that hands an existing browser session to Puppeteer or Playwright via a returned browserWSEndpoint, keeping cookies and state intact across tools. category: Operation tags: - Sessions - Interop - term: Unblock definition: >- The /unblock REST endpoint that performs a single bot-detection- bypass navigation, returning the page after challenges have been cleared. category: Endpoint tags: - REST - Anti-Bot - term: Function definition: >- The /chrome/function and /chromium/function REST endpoints that execute arbitrary user-supplied JavaScript inside a managed browser and return the result. category: Endpoint tags: - REST - Custom Code - term: MCP Server definition: >- The official Browserless Model Context Protocol server at mcp.browserless.io/mcp that exposes browser-agent, smart-scraper, custom-code, downloads, page-export, Lighthouse, and crawl tools to Claude Desktop, Cursor, VS Code, Windsurf, and other MCP clients. category: Integration tags: - MCP - Agents - term: Unit definition: >- The opaque billing unit used by Browserless. Roughly one unit per minute of browser time, plus 6 units per MB of residential proxy bandwidth and 10 units per successful CAPTCHA solve. category: Billing tags: - Billing - Metering - term: Hybrid Automation definition: >- Workflows that combine programmatic browser control with embedded human (or agent) interaction via LiveURL, supporting use cases like manual KYC handoff, two-factor authentication, and bespoke onboarding flows. category: Concept tags: - Hybrid - LiveURL - term: Open Source Image definition: >- The Apache-2.0 licensed browserless/browserless Docker image that underpins the cloud service, free for non-commercial use and self-hostable on the customer's own infrastructure. category: Distribution tags: - OpenSource - Self-Host