Add Browser Env Integration

[filip-michalsky]

Description

Adds BrowserEnv - a unified browser automation integration for the verifiers library supporting two operational modes:

DOM Mode (mode="dom")

• Uses the Stagehand Python SDK for natural language browser control
• Tools: navigate, observe, act, extract - Stagehand's AI-driven primitives
• Ideal for tasks that benefit from semantic understanding of page elements

CUA Mode (mode="cua")

• Vision-based primitives for Computer Use Agent workflows
• Tools: click, double_click, type_text, keypress, scroll, goto, back, forward, wait, screenshot
• Automatic sandbox deployment - CUA server is deployed automatically to sandbox containers
• Three execution modes (fastest to most flexible):
  1. Pre-built image (default): Uses deepdream19/cua-server:latest for ~5-10s startup
  2. Binary upload: Builds and uploads custom server version (~30-60s startup)
  3. Manual server: Connect to locally running CUA server for development

Both modes support local browser execution or Browserbase cloud infrastructure.

What's included:

• verifiers/envs/integrations/browser_env/ - Core integration (BrowserEnv, DOMMode, CUAMode, CUASandboxMode)
• assets/templates/browserbase/cua/ - TypeScript CUA server with Docker build/runtime configs
• environments/browser_dom_example/ - Minimal DOM mode example
• environments/browser_cua_example/ - Minimal CUA mode example
• New [browser] extra: uv add 'verifiers[browser]'

Benchmarks (GAIA, WebVoyager, Mind2Web) have been pushed to Prime Hub under the browserbase/ namespace.

Type of Change

• New feature (non-breaking change which adds functionality)

Testing

# DOM mode
prime eval run browser-dom-example -m openai/gpt-4o-mini

# CUA mode (pre-built image - default, fastest)
prime eval run browser-cua-example -m openai/gpt-4o-mini

# CUA mode (binary upload - custom server)
prime eval run browser-cua-example -m openai/gpt-4o-mini -a '{"use_prebuilt_image": false}'

# CUA mode (manual server for development)
cd assets/templates/browserbase/cua && pnpm dev  # In separate terminal
prime eval run browser-cua-example -m openai/gpt-4o-mini -a '{"use_sandbox": false}'

• All existing tests pass when running uv run pytest locally.
• New tests have been added to cover the changes

Checklist

• My code follows the style guidelines of this project as outlined in AGENTS.md
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• Any dependent changes have been merged and published

Additional Notes

CUA Server Deployment Options:

Mode	Flag	Startup	Use Case
Pre-built image (default)	None	~5-10s	Production
Binary upload	use_prebuilt_image=false	~30-60s	Custom server
Manual server	use_sandbox=false	Instant	Development

Future work:

• Additional benchmark environments available on Prime Hub under browserbase/ org

---

## Bugbot Summary (updated)

```markdown

<!-- CURSOR_SUMMARY -->
---

> [!NOTE]
> Introduces a unified browser automation environment with two modes and a packaged CUA server.
> 
> - Adds `BrowserEnv` with **DOM** (Stagehand SDK: `navigate/observe/act/extract`) and **CUA** (vision primitives: `click/type/scroll/goto/...`) modes
> - CUA mode supports automatic sandbox deployment with options: pre-built Docker image (default), binary upload, or manual local server
> - Implements TypeScript Fastify CUA server (`assets/templates/browserbase/cua/`) with REST endpoints, Dockerfiles, build/publish scripts, and SEA binary tooling
> - Provides example environments (`browser_dom_example`, `browser_cua_example`), docs updates, and a new `[browser]` extra dependency set
> - Adds tests for validation, modes, prompt defaults, response formatting, and example datasets; updates exports to expose `BrowserEnv`
> 
> <sup>Written by [Cursor Bugbot](https://cursor.com/dashboard?tab=bugbot) for commit 38d8ae167778f2e87b708c3f57dec329d010b337. This will update automatically on new commits. Configure [here](https://cursor.com/dashboard?tab=bugbot).</sup>
<!-- /CURSOR_SUMMARY -->

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