Five pages covering the pieces you actually touch in the LangChain 1.x stack: one per package for building an agent, and two for retrieval. Every entry says what the class or function defines or does, links to the official API page (opens in a new tab), and ends with a runnable example whose printed output was verified …

On this page: What langchain is in 1.x Index Pinned versions: langchain==1.4.0 (released 2026-09-03), which resolves langchain-core==1.6.3 (1.6.2 when these examples ran), langgraph==1.2.11 and (for the one live example) langchain-anthropic==1.7.1. Everything below was derived by inspecting these exact installed …

On this page: langchain Packages What langchain-core is Index langchain Packages Version of langchain-core referenced here: langchain-core==1.6.3 (released 2026-09-11). The examples were derived by inspecting the installed package and executed against it on Python 3.13 This page is a part of a five-page set (see how …

On this page: What langgraph is Index Pinned version: langgraph==1.2.11 (released 2026-08-11; it pulls in langgraph-checkpoint 4.2.0, langgraph-prebuilt 1.1.0 and langgraph-sdk 0.4.4; the SqliteSaver example also needs langgraph-checkpoint-sqlite==3.1.1). Everything below was derived by inspecting this exact installed …