Browserbase Changelog

Session replay streaming

Session replays can now be embedded directly in your product and streamed to your end users within seconds of a session ending.

Includes:
- API for embedding session replays in your own product
- Playback in any HLS-compatible player
- Storage, fMP4 encoding, and CDN delivery handled by Browserbase

Your backend fetches the session's .m3u8 playlist from our API, your frontend hands it to a player, and end users stream segments directly from our CDN

Free on every plan, up to 120 sessions per minute.

Learn more

Reduce context bloat in Stagehand 3.4

Stagehand 3.4.0 is live.

Use ignoreSelectors to keep noisy parts of a page out of extract() and observe(): ads, nav, modals, related posts, and anything else your agent should ignore.

const article = await stagehand.extract(
  "extract the article title and body",
  z.object({
    title: z.string(),
    body: z.string(),
  }),
  {
    ignoreSelectors: [".ad", ".newsletter-modal"],
  },
);

Plus:

  • Agent variables are now supported in the Stagehand API schema without the experimental requirement.
  • Agent mode now defaults to hybrid for compatible models and DOM mode otherwise.
  • New CUA model support: openai/gpt-5.4-mini, openai/gpt-5.5, and anthropic/claude-haiku-4-5.
  • Better OOPIF frame handling and stronger observe element ID prompting.

Read the Stagehand docs for extract() and observe().

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 ->