Braintrust alternative | LangWatch

Evals aren’t enough. Your agents need to be simulated.

Stop scoring what already happened. Start preventing it.

Braintrust scores what your AI already did. LangWatch simulates what your agent will do, before it ever reaches a real user. That is the difference between chasing problems and preventing them.

Join thousands of AI developers shipping reliable agents with LangWatch.

How LangWatch compares to Braintrust.

Five things teams care about when picking a quality layer for agents. Each row shows what Braintrust ships today and what LangWatch gives you on day one.

Capability LangWatch Braintrust
01 Full agent simulation suite Not available
02 Eval library + Strong pre-built evaluators Auto-evals
03 Open source + self-hosted Proprietary SaaS
04 Engineers + domain experts Engineers, mostly
05 Voice-native simulation Not available
06 Red teaming, governance, and a gateway Evals and scoring focused

Three reasons agent teams choose LangWatch.

Before Prod / After Prod

Thousands of realistic multi-turn conversations against your full agent stack, before a single user interaction.

AI-powered Ask finds errors and anomalies for you, across flame charts, span lists, topology and graph views, waterfall traces with a full audit trail, and your own saved lenses.

Domain experts build scenarios in the UI. PMs review quality. Legal annotates flagged outputs. All without touching code.

“Auto-evals showed us scores. Simulations showed us where the agent would actually break. That is the gap we needed to close before launch.”
VP Engineering· Healthcare AI platform

94% regressions caught pre-prod
5 min time-to-first-eval
any frameworks supported
$0 cost to start

Stop scoring failures. Start preventing them.

LangWatch is free to start. Connect in minutes, any framework, any model. Agent simulation included on day one.