LangSmith
Unified observability, evaluation, and prompt engineering platform for LLM applications, built by LangChain.
Last verified:
LangSmith is LangChain's commercial platform for tracing, evaluating, and monitoring LLM applications and agents in production, with native OpenTelemetry support and deep integration with the LangChain/LangGraph ecosystem. It offers a free self-serve Developer tier, a usage-based Plus tier, and an Enterprise tier with self-hosted/BYOC deployment on AWS, GCP, or Azure. LangChain Inc., the San Francisco-based company behind it, raised a $125M Series B in October 2025 at a $1.25B valuation.
Pricing
| Tier | Price | Key features |
|---|---|---|
| Developer | $0/monthly | Community support, Basic observability, Self-serve, no credit card required |
| Plus | $39/monthly | Per-seat pricing, unlimited seats, Deployment/Engine features, 1 free small serverless deployment |
| Enterprise | Custom | Custom seats/workspaces, Self-hosted & hybrid (BYOC) deployment, Custom SSO/RBAC, Support SLA |
Source: https://www.langchain.com/pricing
Agent-readiness
- Discoverability
- 80/100
- Machine-readable content
- 90/100
- Programmatic access
- 90/100
- MCP / agent support
- 80/100
- Self-serve transactability
- 80/100
- Transparency
- 70/100
Security & compliance
- SSO / SAML
- Yes
- Encryption at rest
- Yes
- Encryption in transit
- Yes
- Audit log
- Yes
- Pentest report
- Not publicly documented
"Not publicly documented" means Crail found no public evidence either way — not a confirmed absence. See our methodology. Trust center: https://trust.langchain.com.
FAQ
Does LangSmith have a free tier?
Yes, LangSmith offers a free tier or free trial.
Can you buy LangSmith without talking to sales?
Yes, LangSmith can be purchased self-serve without a sales call.
Does LangSmith have an official MCP (Model Context Protocol) server?
Yes, LangSmith publishes an official MCP server (https://github.com/langchain-ai/langsmith-mcp-server).
What compliance certifications does LangSmith hold?
LangSmith holds: SOC 2 Type II.
What people are saying on Reddit & Hacker News
Real, publicly-posted discussion — not a Crail-verified review. Always linked back to the original post so you can read it in context.
“Hey HN. I built this because LangSmith needs a cloud account to see my own traces.”
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“LangSmith’s prompt engineering workflow is okay-ish but a lot of work and gets quite expensive quite fast, and only works for a specific set of prompts (ie one-turn prompts, multi-turn never works).”
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“LangSmith, the platform for prompt authoring/experimentation/observability isn’t great but is useable. I would much prefer Langfuse over it at this point.”
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Reviews
No reviews yet for LangSmith. Be the first to submit a verified review.
Methodology & disclosure
Data verified via agent crawled, last checked 2026-07-26. Agent-readiness methodology version crail-ar-v0.1. No vendor payment influences these scores — see our methodology page.