LangChain (JavaScript)
TypeScript framework for building applications with LLMs, chains, agents and memory.
Agent, MCP and tool libraries npm MIT
Used in agent projects
30
0.2% of 12,697 public repos built with AI coding agents
Rank in agent, mcp and tool libraries
#9 of 9
by use in those projects
Downloads
3.1M
npm, last 7 days, langchain
GitHub stars
18.3K
last push Oct 8, 2026
How LangChain (JavaScript) is used
LangChain (JavaScript) is a dependency in 30 of the 12,697 public GitHub projects set up for AI coding agents that we scanned (0.2%), #9 of 9 in agent, mcp and tool libraries. The most used alternative there is Model Context Protocol SDK (JavaScript). Projects that use it most often also use LangChain.js (86.7%), Zod (60.0%), OpenAI (36.7%).
Often used with LangChain (JavaScript)
| LangChain.js | 86.7% of LangChain (JavaScript) projects · 164.2× more than average |
|---|---|
| Zod | 60.0% of LangChain (JavaScript) projects · 3.5× more than average |
| OpenAI | 36.7% of LangChain (JavaScript) projects · 12.9× more than average |
| TypeScript | 83.3% of LangChain (JavaScript) projects · 1.5× more than average |
| ESLint | 66.7% of LangChain (JavaScript) projects · 1.8× more than average |
| AI SDK | 30.0% of LangChain (JavaScript) projects · 11.6× more than average |
| react-markdown | 30.0% of LangChain (JavaScript) projects · 10.6× more than average |
| dotenv | 43.3% of LangChain (JavaScript) projects · 2.7× more than average |
By coding agent
| Cursor | 0.4% of projects set up for it |
|---|---|
| GitHub Copilot | 0.3% of projects set up for it |
| Claude Code | 0.2% of projects set up for it |
Share of public repos configured for each agent that list LangChain (JavaScript) as a dependency.
Install
| Package | npm install langchain |
|---|---|
| Main stacks | Next.js (15), TypeScript / JavaScript (13), Python (2) |
| Example projects | PaulJPhilp/EffectiveAgent, zkstash/sdk |
Alternatives to LangChain (JavaScript)
| Tool | Used in agent projects | Downloads / wk | GitHub stars | License |
|---|---|---|---|---|
| Model Context Protocol SDK (JavaScript) npm TypeScript SDK for building MCP servers and clients to extend AI agent capabilities. |
603 (4.7%) | 65.4M | 13.5K | MIT |
| Model Context Protocol SDK (Python) pypi Python SDK for building MCP servers and clients to extend AI agent capabilities. |
484 (3.8%) | 60.6M | 24.5K | MIT |
| FastMCP (Python) pypi Fast, Pythonic framework for building MCP servers and clients for AI tool integration. |
169 (1.3%) | 14.3M | 28K | — |
| LangChain (Python) pypi Framework for composing applications with LLMs through chains and agents. |
141 (1.1%) | 37.3M | 148K | MIT |
| LangGraph pypi Framework for building stateful, multi-actor applications with LLMs. |
82 (0.6%) | 12.1M | 43K | — |
| Mastra npm Framework for building AI agents with tools, memory and MCP server support. |
39 (0.3%) | 2M | 28.7K | Apache-2.0 |
| fastMCP (JavaScript) npm TypeScript framework for building Model Context Protocol servers. |
33 (0.3%) | 709K | 3,274 | MIT |