Trace every step your AI takes.
Capture every prompt, completion, tool call, and span. Then search, score, and turn failures into eval test cases.
Free to start · No credit card · 5-min setup
Works with your stack. 50+ integrations, including:
From zero to full tracing in minutes
Two lines to start. Every prompt, span, and score is captured automatically.
Trace every LLM call automatically
Wrap your provider once and every call logs with inputs, outputs, tokens, cost, and latency. No manual instrumentation required.
Score traces and catch regressions
Run LLM-as-judge scorers on live traffic. Filter by score, tag failures, and send them straight into an eval dataset.
Real results from real teams.
<24hrs
To deploy a new frontier model
<10 min
Eval turnaround
50% → 90%+
Accuracy improvement
45x
More feedback
Notion, Dropbox, Zapier, and Coursera use Braintrust to ship better AI.
Tracing built for AI teams.
Every provider in one SDK
Works with OpenAI, Anthropic, Gemini, AWS Bedrock, Azure, and all major frameworks including LangChain, LangGraph, LlamaIndex, CrewAI, and more. No rewrites and no lock-in.
See full agent traces
Tool calls, retrieval steps, and reasoning chains all nest as child spans automatically. See the full decision path for any agent request across services and steps.
Traces become eval datasets
Tag any failing trace and it lands in a dataset. Use the same data structure in production and in evals, so the logs you debug with become the tests you ship with.
Customer spotlight
“Loop helps us understand trace details that would be impossible to scan manually.”
Allen Kleiner, AI Engineering Lead at Retool
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