LangSmith
Developer plan ($0): 1 seat and up to 5k base traces a month for LLM and agent observability and evals.
Dev Tools
What you get
Tracing, evaluation and prompt tools for LLM apps and agents, with up to 5k base traces a month for one user.
How to get it
Choose Start for free on langchain.com/pricing.
The catch
Only 1 seat, base traces are kept 14 days, and usage past 5k traces is billed pay as you go.
From the official page · checked Oct 22, 2026