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LangSmith

Platform by LangChain, Inc.

ActiveClosed sourceVerified Oct 22, 2026
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Hosted platform from LangChain for tracing, evaluating, and deploying LLM applications and agents, usable with or without LangChain/LangGraph.

Key facts

Type
Platform · Web, Self-hosted
Pricing
Free tier, paid from $39/mo
Free tier
Developer plan: $0, 1 seat, 5k base traces/month, then pay-as-you-go; cloud only, no deployments.
License
Proprietary
Models
Framework- and model-agnostic tracing, OpenAI, Anthropic, Google, Integrations for LangChain, LangGraph, CrewAI, Pydantic AI, Vercel AI SDK, OpenTelemetry
Languages
Python, TypeScript, Go, Java
Platforms
Web, macOS, Windows, Linux
Bring your own API key
Yes
Local models
Yes
MCP support
Yes
Self-hostable
Yes

LangSmith pricing

Developer

$0/month

1 seat; 5k base traces/month then pay-as-you-go; cloud only

Plus

$39/month

Per seat per month, billed monthly; 10k base traces/month then pay-as-you-go; 1 free small serverless deployment; no yearly price listed

Enterprise

Custom

Contact sales; invoiced annually; cloud, hybrid, or self-hosted in your VPC

Best for

  • Teams that need tracing and evaluation for LLM apps in production
  • LangChain/LangGraph users who want integrated observability and deployment
  • Organizations that need a self-hosted observability option (Enterprise)

Pros

  • Works with many frameworks and providers, not only LangChain
  • Combines tracing, evals, prompt management, and agent deployment in one product
  • OpenTelemetry ingestion and a hosted remote MCP server
  • Cloud, hybrid, and self-hosted options

Cons

  • Platform is closed source; self-hosting requires an Enterprise license
  • Per-seat pricing on Plus plus metered usage can be hard to forecast
  • Free Developer plan is limited to one seat
Sources (12)