Building applications with LLMs through composability
Go to file
湛露先生 c87a270e5f
cookbook: Fix docs typos. (#30763)
Thank you for contributing to LangChain!

- [ ] **PR title**: "package: description"
- Where "package" is whichever of langchain, community, core, etc. is
being modified. Use "docs: ..." for purely docs changes, "infra: ..."
for CI changes.
  - Example: "community: add foobar LLM"


- [ ] **PR message**: ***Delete this entire checklist*** and replace
with
    - **Description:** a description of the change
    - **Issue:** the issue # it fixes, if applicable
    - **Dependencies:** any dependencies required for this change
- **Twitter handle:** if your PR gets announced, and you'd like a
mention, we'll gladly shout you out!


- [ ] **Add tests and docs**: If you're adding a new integration, please
include
1. a test for the integration, preferably unit tests that do not rely on
network access,
2. an example notebook showing its use. It lives in
`docs/docs/integrations` directory.


- [ ] **Lint and test**: Run `make format`, `make lint` and `make test`
from the root of the package(s) you've modified. See contribution
guidelines for more: https://python.langchain.com/docs/contributing/

Additional guidelines:
- Make sure optional dependencies are imported within a function.
- Please do not add dependencies to pyproject.toml files (even optional
ones) unless they are required for unit tests.
- Most PRs should not touch more than one package.
- Changes should be backwards compatible.
- If you are adding something to community, do not re-import it in
langchain.

If no one reviews your PR within a few days, please @-mention one of
baskaryan, eyurtsev, ccurme, vbarda, hwchase17.

Signed-off-by: zhanluxianshen <zhanluxianshen@163.com>
2025-04-10 09:13:24 -04:00
.devcontainer community[minor]: Add ApertureDB as a vectorstore (#24088) 2024-07-16 09:32:59 -07:00
.github [ci]: Quick codspeed.yml tweaks to enable comparisons with master (#30752) 2025-04-09 13:13:49 -04:00
cookbook cookbook: Fix docs typos. (#30763) 2025-04-10 09:13:24 -04:00
docs dosc: Fix typo in get_separators_for_language method section (#30748) 2025-04-09 13:03:01 -04:00
libs community: deprecate AzureCosmosDBNoSqlVectorSearch in favor of langchain-azure-ai implementation (#30756) 2025-04-09 21:04:16 +00:00
scripts infra: update mypy 1.10, ruff 0.5 (#23721) 2024-07-03 10:33:27 -07:00
.gitattributes Update dev container (#6189) 2023-06-16 15:42:14 -07:00
.gitignore [performance]: Adding benchmarks for common langchain-core imports (#30747) 2025-04-09 13:00:15 -04:00
.pre-commit-config.yaml docs: fix builds (#29890) 2025-02-19 13:35:59 -05:00
.readthedocs.yaml docs(readthedocs): streamline config (#30307) 2025-03-18 11:47:45 -04:00
CITATION.cff rename repo namespace to langchain-ai (#11259) 2023-10-01 15:30:58 -04:00
LICENSE Library Licenses (#13300) 2023-11-28 17:34:27 -08:00
Makefile langchain: clean pyproject ruff section (#30070) 2025-03-09 15:06:02 -04:00
MIGRATE.md Proofreading and Editing Report for Migration Guide (#28084) 2024-11-13 11:03:09 -05:00
poetry.toml multiple: use modern installer in poetry (#23998) 2024-07-08 18:50:48 -07:00
pyproject.toml langchain: clean pyproject ruff section (#30070) 2025-03-09 15:06:02 -04:00
README.md [performance]: Adding benchmarks for common langchain-core imports (#30747) 2025-04-09 13:00:15 -04:00
SECURITY.md docs: single security doc (#28515) 2024-12-04 18:15:34 +00:00
uv.lock Clean up numpy dependencies and speed up 3.13 CI with numpy>=2.1.0 (#30714) 2025-04-08 09:45:07 -04:00
yarn.lock box: add langchain box package and DocumentLoader (#25506) 2024-08-21 02:23:43 +00:00

LangChain Logo

Release Notes CI PyPI - License PyPI - Downloads GitHub star chart Open Issues Open in Dev Containers Twitter CodSpeed Badge

Note

Looking for the JS/TS library? Check out LangChain.js.

LangChain is a framework for building LLM-powered applications. It helps you chain together interoperable components and third-party integrations to simplify AI application development — all while future-proofing decisions as the underlying technology evolves.

pip install -U langchain

To learn more about LangChain, check out the docs. If youre looking for more advanced customization or agent orchestration, check out LangGraph, our framework for building controllable agent workflows.

Why use LangChain?

LangChain helps developers build applications powered by LLMs through a standard interface for models, embeddings, vector stores, and more.

Use LangChain for:

  • Real-time data augmentation. Easily connect LLMs to diverse data sources and external / internal systems, drawing from LangChains vast library of integrations with model providers, tools, vector stores, retrievers, and more.
  • Model interoperability. Swap models in and out as your engineering team experiments to find the best choice for your applications needs. As the industry frontier evolves, adapt quickly — LangChains abstractions keep you moving without losing momentum.

LangChains ecosystem

While the LangChain framework can be used standalone, it also integrates seamlessly with any LangChain product, giving developers a full suite of tools when building LLM applications.

To improve your LLM application development, pair LangChain with:

  • LangSmith - Helpful for agent evals and observability. Debug poor-performing LLM app runs, evaluate agent trajectories, gain visibility in production, and improve performance over time.
  • LangGraph - Build agents that can reliably handle complex tasks with LangGraph, our low-level agent orchestration framework. LangGraph offers customizable architecture, long-term memory, and human-in-the-loop workflows — and is trusted in production by companies like LinkedIn, Uber, Klarna, and GitLab.
  • LangGraph Platform - Deploy and scale agents effortlessly with a purpose-built deployment platform for long running, stateful workflows. Discover, reuse, configure, and share agents across teams — and iterate quickly with visual prototyping in LangGraph Studio.

Additional resources

  • Tutorials: Simple walkthroughs with guided examples on getting started with LangChain.
  • How-to Guides: Quick, actionable code snippets for topics such as tool calling, RAG use cases, and more.
  • Conceptual Guides: Explanations of key concepts behind the LangChain framework.
  • API Reference: Detailed reference on navigating base packages and integrations for LangChain.