[bot] Instrument Stagehand (1,250,942 weekly downloads)

[braintrust-bot]

Summary

@browserbasehq/stagehand (Browserbase) is an LLM-driven browser automation SDK for JS/TS. It wraps Playwright with four LLM-reasoning primitives that agents call directly: act(), extract(), observe(), and agent(). Each of these makes model calls (reasoning over an accessibility-tree/DOM representation to decide actions, extract structured data, or run a multi-step autonomous task) — this is a genuine "agent execution" surface, not just browser control. This repository has zero instrumentation for any Stagehand execution surface: no wrapper, no channel/plugin, no auto-instrumentation config, no e2e scenario.

What instrumentation is missing

SDK Surface	Description
page.act(instruction)	Executes a browser action from a natural-language instruction, backed by an LLM call resolving the instruction to a concrete action
page.extract({ instruction, schema })	Extracts structured data from the page via an LLM call against a provided schema
page.observe(instruction)	Discovers candidate actionable elements on the page via an LLM call
stagehand.agent(options).execute(task)	Runs an autonomous multi-step agent loop (its own model/tool-call loop) to complete a task end-to-end

None of these are covered by any existing plugin, wrapper, or auto-instrumentation config in this repo.

Braintrust docs status

not_found. Checked https://www.braintrust.dev/docs and the full integrations index at https://www.braintrust.dev/docs/integrations (AI Providers, SDK Integrations, Agent Frameworks, Developer Tools sections). Stagehand and Browserbase are not mentioned anywhere in the docs.

Weekly downloads

Weekly downloads: 1,250,942 (as of 2026-08-02; https://api.npmjs.org/downloads/point/last-week/@browserbasehq/stagehand)

Upstream references

• npm package: https://www.npmjs.com/package/@browserbasehq/stagehand
• Official GitHub repo: https://github.com/browserbase/stagehand
• Official docs: https://docs.stagehand.dev/first-steps/introduction
• Marketing/product site: https://www.stagehand.dev/
• Releases (active, e.g. stagehand/server-v3 v3.7.4 on Jul 21, v3.7.3 on Jul 16, @browserbasehq/stagehand@3.7.0 on Jul 13): https://github.com/browserbase/stagehand/releases

Local files inspected

• js/src/auto-instrumentations/configs/ — no Stagehand config entry among any files
• js/src/instrumentation/plugins/ — no Stagehand channels or plugin file
• js/src/wrappers/ — no Stagehand wrapper
• e2e/scenarios/ — no Stagehand-specific test scenario
• Full repo grep (case-insensitive) for stagehand|browserbasehq — zero matches anywhere in the repository, including all pnpm-lock.yaml files (not even present as a transitive dependency)
• js/src/instrumentation/config.ts — InstrumentationIntegrationsConfig has no Stagehand-related key