Browserbase Changelog

Improved Downloads API

New and improved Downloads API

Every file your agent downloads is now individually addressable.

What changed?

The Downloads API now treats every file as a first-class object with its own ID and metadata. You can list downloads for a session and filter by filename, MIME type, size, or timestamp; fetch an individual file or just its metadata; and delete a single file on demand.

The session-level zip endpoint continues to work, no migration required. Your existing downloads are already addressable.

Read the docs →

Verified agents with Stagehand

Stagehand 3.3.0 is live.

Verified mode for improved agent identity. Sessions get a verifiable identity that helps on sites that gate bot traffic. Enable in your session params:

const stagehand = new Stagehand({
  env: "BROWSERBASE",
  browserbaseSessionCreateParams: {
    browserSettings: {
      verified: true,
    },
  },
});

Plus:

  • Adaptive thinking with Anthropic models. Claude CUA now scales the extended-thinking budget to match task complexity — faster on simple steps, deeper when it counts.
  • Agent usage in stagehand.metrics. agent.execute() calls now contribute to stagehand.metrics on API-backed sessions, so token counts and model calls land where you expect them.
  • Strict structured outputs. Supported model paths now use strict JSON schema enforcement, eliminating malformed responses on extract() and other structured calls.
  • Clearer file upload elements. File inputs are now explicit in the page snapshot, so agents can identify and drive upload flows reliably.

Use Stagehand with any model

Managing model providers adds friction to every Stagehand setup: separate API keys, accounts, rate limits, and tier gating. Model Gateway removes that layer.

Pass your Browserbase API key and pick a model. We handle routing, retries, and billing at market price with no markup.

const stagehand = new Stagehand({
   apiKey: process.env.BROWSERBASE_API_KEY,
   model: "openai/gpt-5", // or “anthropic/claude-sonnet-4-6” / “google/gemini-3-flash-preview”
});

Switching models is a one-line change. No new accounts, no reworked setup. Rate limit handling, retries, and action caching all run through Browserbase automatically.

Supported: OpenAI, Anthropic, Gemini. Need something else? Reach out.

Train and Evaluate browser agents with Browserbase & Prime Intellect

Browserbase and Prime Intellect have partnered to make browser agent training more accessible. You get scalable browser environments, live website access, and the full Browserbase platform as your training substrate with Prime Intellect’s full training platform.

BrowserEnv, the reinforcement learning environment built on this foundation, is available today at browserenv.com.

Browserbase Search

Most web agents need to be able to search the web before performing actions on a website. Browserbase Search, powered by Exa, now handles searching with a single API call.

Send a plain-text query and get back the URLs your agent needs to act on next.

import { Browserbase } from "@browserbasehq/sdk";

const bb = new Browserbase({ apiKey: process.env.BROWSERBASE_API_KEY! });

const searchResponse = await bb.search.({
  query: "browserbase documentation",
  numResults: 10,
});

Results return a url, title, and description, up to 25 results.

Each plan includes 1,000 free searches.

Learn more

MCP Server now runs on our infrastructure

We migrated the hosted version (SHTTP) of the Browserbase MCP server onto Browserbase-managed infrastructure to improve reliability and make ongoing updates easier.

If you are using MCP in Cursor, Claude Desktop, or another MCP client, no action is required. Keep following our setup guide to connect

What changed

  • MCP is now served from Browserbase-managed endpoints.
  • Improved stability for longer-running MCP sessions.

The Browserbase Fetch API is available today

Introducing, the Fetch API for Browserbase. Give us a URL and we return the page content with no browser session required. It’s fast, cheap, (~$1 / 1k pages), and perfect for agents that just need to read the web.

Get started today: docs.browserbase.com/features/fetch

const res = await bb.fetchAPI.create({
  url: "https://browserbase.com/",
});

Stagehand Caching

Stagehand now caches the results of repeated actions, eliminating redundant LLM calls automatically, no code changes required.

When Stagehand encounters a page structure it’s seen before, it serves the cached result instantly, no LLM call needed. DOM hashing validates each match, so accuracy stays high even as cache usage scales.

The result: up to 2x faster execution and ~30% cost reduction on repeat workflows. Your agents get more efficient the more they run.

Caching is conservative by default and scoped to your project. It kicks in automatically for all Stagehand users on Browserbase.

Read the docs →

Browserbase on the Vercel Marketplace

Browserbase is now a one-click integration on the Vercel Agent Marketplace. Your agents get production-grade browsers without running browsers themselves.

Agents deployed on Vercel Sandbox can connect to remote browsers over CDP, keeping your agent logic on Vercel while the browser runs on infrastructure built for automation. One API key, unified billing, no proxies or complex configuration. The integration also works alongside Vercel’s AI Gateway and Sandbox out of the box.

We’re also launching Web Bot Auth support with Vercel. Browserbase agents now send cryptographically signed requests that Vercel verifies, so your agents can reliably browse Vercel-hosted deployments without getting blocked by security layers.

Read more ->

Browserbase Functions

Functions let you deploy agents and automations directly to Browserbase and run it next to the browser session it controls. You define, deploy, and invoke a function, and Browserbase handles execution, browser lifecycle, and results as one system.

What this means:

  • Lower latency, up to 70% faster
  • Fewer moving parts and less infrastructure to manage
  • Async and long-running executions with results tied directly to real browser sessions.
  • Local development mirrors production using real Browserbase sessions.

Available now in TypeScript (documentation)

npx @browserbasehq/sdk-functions init

Session Recordings

We’ve completely rebuilt session recordings from the ground up.

Instead of DOM-based replay, Browserbase now records what the browser actually renders using a CDP-based screencast. This makes replays deterministic, accurate, and trustworthy.

What’s new:

  • Pixel-accurate screen recordings (no DOM reconstruction)
  • Event-driven frame capture (records only when the screen changes)
  • Asynchronous, constant-time video encoding using HLS
  • Seamless multi-tab playback with a shared global timeline
  • Secure, signed segment delivery with CDN enforcement
  • Just-in-time encoding to keep costs low and playback fast

If you tried our old session replays and lost trust in them, this rebuild is for you.

Read more here: https://www.browserbase.com/blog/session-recordings