Listed whether or not they pay us. Prices from each tool's own pricing page, checked Oct 16, 2026.

LangSmith

LangChain's platform for tracing, evaluating, and deploying LLM apps and agents, framework agnostic.

Best for LangChain/LangGraph teams shipping agents

What it does

LangSmith is an agent engineering and observability platform that helps teams trace, evaluate, and monitor their AI applications. Developers send in execution runs and multi turn interactions from their agent frameworks, and LangSmith outputs step by step visibility, performance analytics, and automated failure detection. It is designed for developers and engineering teams building and deploying AI agents.

Read more: 3 features and how people use themShow less

  1. Agent tracing

    Records multi turn chats and runs step by step so you can pinpoint issues impacting latency, cost, and response quality across popular frameworks.

    Use caseA developer tracks down an unexpected hallucination by inspecting the full execution trace and tool calls of an agent.

    From langchain.com/langsmith
  2. LangSmith: Automated insights

    Automated insights

    Analyzes and groups traces automatically using unsupervised topic clustering to identify common behaviors and failure modes.

    Use caseA software team reviews an executive summary and clustered error templates to detect recurring agent failure patterns.

    From langchain.com/langsmith · image from LangSmith

  3. LangSmith deployment

    Runs and manages long running agents on purpose built infrastructure supporting scale to zero serverless configurations or dedicated autoscaling replicas.

    Use caseA cloud engineer deploys a background agent using a serverless deployment that scales down when idle to conserve compute.

    From langchain.com/pricing

Written from LangSmith's own website, checked . Each feature links to the page it comes from; images are LangSmith's own.

Every plan

PlanMonthlyBilled yearlyPerWhat it includes
Free (Developer)FreeNot listedper seat (1 seat max)5k base traces/mo, then pay as you go; community support
Plus$39Not listedper seat10k base traces/mo, unlimited seats, 1 free small deployment; overage ~$5 per 1k base traces (0.005 LSU)
EnterpriseNot listedNot listedper seatcontact sales; hybrid or self hosted, SSO, RBAC, SLA

From LangSmith's own pricing page, checked . Prices are in US dollars per month; "billed yearly" is the monthly price when you pay for a year up front. A few figures (often the yearly price) are derived rather than printed on the page.

Before you pay

Trains on your data
No
What LangSmith saysWe will not train on your data, and you own all rights to your data. Source page
Data retention
Traces upgraded to extended retention are kept for 180 days by default, which can be customized for Enterprise customers.
What LangSmith saysTraces upgraded to extended retention (180 days by default as of September 14, 2026, customizable for Enterprise customers). Source page
Export your data
Yes
What LangSmith saysBulk data export Source page
Discounts
Discounted rates and up to $10,000 in credits for VC backed startups.
What LangSmith saysWe offer discounted rates and credits for VC backed startups. Get up to $10,000 in credits. Source page
Support
Community Forum, Support Portal, Email Support, Slack
What LangSmith saysCommunity Forum Support Portal Email Support Slack Source page

Only what LangSmith's own pages state, with the quote behind each answer. Anything they don't publish is left out rather than guessed.

Getting started with LangSmith

  1. Sign up for an account at smith.langchain.com using Google, GitHub, or email without needing a credit card.
  2. Navigate to the Settings page, open API Keys, and click Create API Key to generate and save your key.
  3. Set up tracing in your application using environment variables, framework integrations, or the SDK.

Written from LangSmith's own help pages: docs.langchain.com/langsmith/observability

LangSmith video tutorials

LangSmith explained in 5 minutesLangChain · 6 min
LangSmith Tutorial - LLM Evaluation for BeginnersDave Ebbelaar · 36 min
LangSmith in 5 Minutes (Clearly Explained)Cloud X Berry · 6 min

Independent creators on YouTube, not LangSmith or us. The video loads from YouTube only when you press play.

What the free plan includes

Developer: 1 seat, 5k base traces/month, 14 day base trace retention

Questions people ask about LangSmith

How much does LangSmith cost?

Paid plans start at $39 a month (Plus). 3 plans are listed above, from LangSmith's own pricing page.

Is LangSmith free?

Yes, there is a free plan: Developer: 1 seat, 5k base traces/month, 14 day base trace retention.

Does LangSmith train its AI on my data?

No, the company says your data is not used for training. Source

Does LangSmith have a student or other discount?

Discounted rates and up to $10,000 in credits for VC backed startups. Source

Does LangSmith have an API?

Yes.

When will I be billed?

Developer and Plus plan seats are billed monthly on the 1st or pro rated mid month, with traces billed monthly in arrears, whereas Enterprise plans are invoiced annually upfront. Source

What is a seat?

A seat represents a distinct user within your organization, based on the total count of users including invited members. Source

Do you offer a plan for startups?

Early stage companies building agentic applications can access discounted rates and generous free trace allotments through the Startup Plan. Source

Works with

AI models
OpenAI, Anthropic, gpt 6 luna

Where this came from

Plans, prices and limits were copied from LangSmith's own pages and the other sources listed, then checked .

How we collect prices and rank tools · Is something wrong? Correct this listing

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