LangChain.js
JavaScript and TypeScript framework of interoperable components for building LLM apps and agents, with LangGraph.js and Deep Agents above it.
Harness by LangChain
Install
From the package registry. Read the repository before you give any tool access to your data.
npm install langchain
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About
Use cases: agent-orchestration, knowledge-base
Reviews
Write a reviewNo reviews yet. Installed it? Reviews come from verified installers only. How reviews work
Fact sheet
- Languages
- TypeScript, JavaScriptREADME
- Packages
- langchain (npm)README
- Observability
- LangSmithREADME
- Deploys to
- langsmith-deploymentREADME
- Maturity
- Betagithub.com
Facts extracted by Claude Sonnet 5.5 from the linked sources on Oct 24, 2026; reviewed Oct 24, 2026. Wrong fact? Tell us.
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Featured in
Signals
- Stars
- 18,292
- Forks
- 3,455
- Open issues
- 271
- Last commit
- Oct 23, 2026 (3 days ago)
- Last release
- Oct 22, 2026 (4 days ago)
From GitHub (fetched Oct 24, 2026).
Details
- Packages
- npm
langchain - License
- MIT
- Repository
- github.com/langchain-ai/langchainjs
- First seen
- Oct 24, 2026
- Last checked
- Oct 24, 2026
- Source
- DocsREADMEgithub-graphql
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Cite this page
LangChain.js. Agent Mart. https://agentmart.dev/harnesses/langchain-js (last updated 2026-10-24)