# How Browserbase uses Braintrust

**100,000s**: “100,000s of public eval dashboard views”

As published on [braintrust.dev](https://www.braintrust.dev/customers/browserbase). Captured by usedby on 2026-10-09.

- Company: [Browserbase](https://www.usedby.ai/companies/browserbase.md)
- Tool: [Braintrust](https://www.usedby.ai/tools/braintrust.md)
- Industry: [DevTools & Infrastructure](https://www.usedby.ai/companies/industry/devtools-infrastructure.md)
- Teams: engineering team

## What the story says

Browserbase, which provides infrastructure for AI agents to browse the web, uses Braintrust to add model observability on top of browser session replay and to power public benchmarks and evals for its open source Stagehand SDK. This helps it and its customers measure browser agent reliability and choose the best model.

Summary written by usedby from the source page, in English. The figures are those of Braintrust and Browserbase, not ours.

> Browserbase maintains Stagehand, an open source SDK that provides a unified tool interface for agents to control browsers in TypeScript, Python, Go, and other languages. Alongside Stagehand, the team publishes benchmarks and evals powered by Braintrust that show which models perform best at browser tasks.

> This is an important value for our customers because they don't know which model to choose. When we run all of these benchmarks and evals against Stagehand, it makes it really easy for our customers to know which model's going to work best.
>
> Paul Klein IV, Founder & CEO

Source: [braintrust.dev](https://www.braintrust.dev/customers/browserbase), captured 2026-10-09.

> Braintrust shows us the model's input and output and what actions it took.
>
> Paul Klein IV, Founder & CEO

Source: [braintrust.dev](https://www.braintrust.dev/customers), captured 2026-10-06.

> What we're often missing is, what was the model thinking? That's where Braintrust comes in.
>
> Paul Klein IV, Founder & CEO

Source: [braintrust.dev](https://www.braintrust.dev/customers), captured 2026-10-06.

## What usedby checked

We compared the story with its live page on 2026-10-09.

- Checked: the figure 100,000s is printed word for word on the page, near the name of Browserbase.
- Checked: the passage quoted above is copied word for word from the page, near the name of Browserbase.
- Checked: Browserbase uses Braintrust. Confirmed line. Latest check across sources: 2026-10-09.
- Not checked: the result itself. We quote it; we did not measure it.

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Source: https://www.usedby.ai/case-studies/browserbase-braintrust · How we check: https://www.usedby.ai/methodology