LangChain API Reference FAQ
How many classes, methods, and decorators are in the LangChain API reference?
This LangChain API reference documents 32 classes, 31 methods, and 8 decorators, for 71 pages in total. Each entry has its own page covering what it does, its parameters, runnable code examples, common mistakes, and guidance on when not to use it.
How do I search the LangChain API reference?
Use the search box at the top of the page to filter by name across classes, methods, and decorators, and use the Classes, Methods, and Decorators tabs to browse one category at a time. Filtering happens instantly in the browser, so results narrow as you type with no page reload.
What does each LangChain reference page include?
Every reference page includes a plain-language explanation of what the class, method, or decorator does, its parameters and signatures, copy-paste code examples, common mistakes to avoid, and notes on when not to reach for it. The goal is to answer practical usage questions, not just restate signatures.
What is the difference between the class, method, and decorator pages?
Class pages document LangChain objects you instantiate, such as loaders, splitters, and vector stores, including their package and purpose. Method pages document functions you call on those objects and note what they apply to. Decorator pages document decorators like tool definitions and note the module they come from.
Is this the official LangChain API documentation?
No. This is an independent, hand-written reference from DevShelfHub designed to be searchable and beginner-friendly with examples and common mistakes. Always check the official LangChain docs for the exact current signatures, because the library evolves quickly across versions.
Which LangChain package version does this reference cover?
The reference targets the modern langchain and langchain-core packages and their split community and partner packages, such as langchain-community and langchain-openai. Because LangChain changes frequently, confirm import paths against the version you have installed before copying examples into production.