What is LangChain?
The framework for building agents, with LangGraph and LangSmith.
Who is LangChain best for?
LangChain is best for engineering teams who build AI agents on any model provider and want tracing and hosting too.
Getting a first agent running
The langchain library ships a ready-made agent setup and integrations for many models and tools, so you write less glue code.
Agents that need tight control
LangGraph gives low-level control over each step for production agents where behaviour has to be predictable.
Debugging and testing agents
LangSmith records every step of a run as a trace and turns traces into datasets for online and offline evals.
Hosting long-running agents
LangSmith Deployment keeps state between runs, exposes 30+ API endpoints and schedules jobs with cron.
How much does LangChain cost?
LangChain's open-source framework is free, and its LangSmith platform has a free Developer plan for one user, then Plus at $39 per seat per month plus pay-as-you-go usage.
- One seat
- 5,000 base traces a month included
- Community support
- 10,000 base traces a month included
- Unlimited seats
- Deployment and Engine, with one small serverless deployment free
These are LangSmith plans; the LangChain, LangGraph and deepagents libraries are open source and free. Usage beyond each allowance is billed in LangChain Compute Units at $1.50 each and LangChain Storage Units at $1.00 each, and each extra trace uses 0.005 LSU. Base traces are kept for 14 days, or 400 days as extended traces for an extra fee. Enterprise has custom pricing on an annual invoice, with self-hosted or hybrid hosting, custom SSO and a support SLA. VC-backed startups can apply for discounted rates and up to $10,000 in credits. Full pricing on langchain.com. We checked these prices on .
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Is LangChain open source?
Yes. LangChain's code is public under the MIT licence, so you can read it, change it and run it yourself.
On GitHub
149,419stars
- Last commit
- 12 Nov
- Repository age
- 4 years
- Latest release
- 11 Nov
- Licence
- MIT
- Self-hosted
- No
- Repository
- langchain-ai/langchain
What are the best LangChain alternatives?
Three tools on Recaply do LangChain's job.
Questions about LangChain
What is LangChain?
The framework for building agents, with LangGraph and LangSmith.
Who is LangChain for?
LangChain is best for engineering teams who build AI agents on any model provider and want tracing and hosting too.
Is LangChain free?
Yes. The LangChain framework is open source under the MIT license and free to use. LangSmith, the company's platform for tracing, evals and deployment, also has a free Developer plan with one seat and 5,000 base traces a month.
How does LangSmith pay-as-you-go pricing work?
LangSmith bills usage beyond your plan in two units: LangChain Compute Units at $1.50 each for work such as Engine runs, Fleet agents, deployments and sandboxes, and LangChain Storage Units at $1.00 each for traces and storage. Each extra trace uses 0.005 LSU.
Is LangChain open source?
Yes. LangChain's code is public under the MIT licence, so you can read it, change it and run it yourself.
What are the best LangChain alternatives?
The closest alternatives on Recaply are Agno, Genkit and Smolagents.
Where can I try LangChain?
On its official website, langchain.com.
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