Agent Evals

Know if your agent works

Run evals before and after shipping, iterate on prompts, and gather expert feedback.

Test with offline evaluations on datasets or run online evaluations on production traffic. Offline evals. Online evals. Multi-turn evals. Drive iteration speed with LangSmith evals.

Try LangSmith free. No credit card required.

LangSmith dashboard showing agent evaluation metrics

How LangSmith evaluation works

1

Build your dataset

Turn production traces into curated evaluation datasets. Start from real user interactions, not synthetic examples.

2

Run evals on every change

Test offline before shipping and score live traffic in real-time. Catch regressions before users report them.

3

Iterate with confidence

Compare prompt versions, model providers, and agent configurations side by side. Ship the version you can prove is better.

LangSmith powers top engineering teams, from AI startups to global enterprises

Zip
Writer
Harvey
Vanta
Abridge
Clay
Rippling
Mercor
Listen Labs
dbt Labs
Klarna
Headspace
Lyft
Coinbase
Rakuten
LinkedIn
Elastic
Workday
Monday.com

Built for Production Agent Evaluation

Teams trust LangSmith to evaluate their most important agent applications

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LLM Calls Traced
1B+
Events Ingested per Day
100K+
Monthly active orgs in LangSmith SaaS

LangSmith Agent Engineering Platform

Get complete visibility to drive agent performance and improvement

Agents create dense outputs that make debugging hard. Tracing gives you clear visibility into each step, so you can confidently explain what your agent is actually doing.

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LangSmith Observability interface showing trace details

Built for Enterprise

Security and compliance at scale

LangSmith meets the demanding security, performance, and collaboration requirements of large organizations building AI applications at scale.

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Granular permissions

Role-based access control with org-level permissions and project isolation to meet your security and compliance requirements.

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SOC 2 Type II

Third-party security certification with comprehensive security controls.

Trust center
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Self-hosted deployment

Self-hosting options to maintain full control over your AI data and meet strict compliance requirements.

Why top AI teams choose LangSmith

Visibility & control

See exactly what's happening at every step of your LLM application. Debug issues and understand behavior instantly.

Fast iteration

Rapidly move through build, test, deploy, learn, repeat with workflows across the entire LLM engineering lifecycle.

Framework neutral

Keep your current stack. LangSmith works with your preferred open-source framework or custom code.

Customers

Elastic

"Working with LangSmith on the Elastic AI Assistant had a significant positive impact on the overall pace and quality of our development and shipping experience. We couldn't have delivered the product experience our customers now have without LangSmith—and we couldn't have done it at the same pace without it."

James Spiteri, Director of Security Product Management at Elastic

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Rakuten

"What we really needed was a more structured way to test new approaches, something better than just shipping and seeing what happened. LangSmith gave us a more scientific, structured way to understand what was actually working, whether that meant running pairwise evaluations or digging into why accuracy jumped from 70% to 80%. Our engineers especially love the intuitive debugging experience, it's saved us a lot of time."

Yusuke Kaji, General Manager of AI for Business Development at Rakuten

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Get a Demo of LangSmith

See how LangSmith can help you evaluate your AI agents with offline evals, online evals, and multi-turn testing.