The easiest way to add LLM observability to your AI app (2026)

Braintrust offers a streamlined approach to incorporating LLM observability into AI applications via its CLI, which simplifies the process by handling authentication, SDK setup, instrumentation, verification, and trace access in a single workflow. It allows engineering teams to achieve live trace visibility in approximately five minutes, making it a rapid solution compared to other tools that require extensive setup and maintenance. The CLI supports Python and TypeScript projects, automatically instruments LLM calls without code changes, and provides a direct path from trace collection to evaluation, integrating cost analysis, online scoring, and CI evaluations into one workflow. Braintrust's free tier permits testing with real production traffic, providing 1 GB of processed data monthly. The tool is particularly advantageous for teams prioritizing setup speed and integration with evaluation workflows, while alternatives like Langfuse and PostHog offer different features that may suit teams with distinct infrastructure needs or existing analytics frameworks.