@braintrust/browser

Braintrust Browser SDK

Official browser-only SDK for Braintrust.

This is an integration package that provides browser-optimized builds of the Braintrust SDK with AsyncLocalStorage polyfill support for standard browsers.

This package supports limited functionality in the browser. There is a known CORS limitation when used outside the braintrust.dev domain. If you need this for your own domain, contact [e-mail].

Installation

npm install @braintrust/browser braintrust
# or
pnpm add @braintrust/browser braintrust
# or
yarn add @braintrust/browser braintrust

Note: Install both packages so your browser integration and main SDK stay on compatible versions.

Requirements

• braintrust (installed alongside @braintrust/browser)
• zod (^3.25.34 || ^4.0)

Quickstart

import * as braintrust from "@braintrust/browser";

const experiment = await braintrust.init("BrowserExperiment", {
  apiKey: "YOUR_API_KEY",
});

// Use tracing in browser
const result = await braintrust.traced(
  async () => {
    // Your code here
    return "result";
  },
  { name: "myOperation" },
);

Notes

Use @braintrust/browser when:

• Building browser-only applications
• Needing AsyncLocalStorage support in standard browsers

Use braintrust directly when:

• Building Node.js applications
• Using Next.js or other full-stack frameworks
• Needing CLI tools or filesystem access

Browser-compatible features include:

• Logging and tracing
• Experiments and datasets
• Prompt management
• AI provider wrappers (OpenAI, Anthropic, Google)
• Evaluation framework
• OpenTelemetry integration

Documentation

For full documentation, visit https://www.braintrust.dev/docs

License

Apache-2.0