Mason Daugherty f7e87f7ab8 feat(model-profiles): plain-English summary for profile refresh PRs (#38218)
Automated model-profile refresh PRs (e.g. #38210) ship a static template
body, so a reviewer has to open *Files changed* and read large blocks of
generated data to learn what actually moved. Because the underlying
profile data is fully structured, we can describe the changes
deterministically — no LLM, no hallucination risk.

This adds a `langchain-profiles summarize` subcommand that compares the
working-tree `_profiles.py` files against a git ref and renders a
skimmable Markdown summary: models added (with a short capability
descriptor), models removed, and per-field capability changes
(context/output tokens, modalities, tool calling, reasoning, etc.),
grouped by provider and capped so huge refreshes stay readable. Profiles
are read with `ast.literal_eval` rather than imported, so the generated
data file is never executed.

Example output for a refresh that adds a model and bumps an output
limit:

```
## Summary of changes

**1 added · 0 removed · 1 changed** across 1 provider(s).

### openai

** 1 added**
- `gpt-6-preview` — 1,000,000 ctx, 128,000 out, text+image+audio in, reasoning, tools

**✏️ 1 changed**
- `gpt-3.5-turbo`: max output tokens 4,096 → 16,384
```

Made by [Open
SWE](https://openswe.vercel.app/agents/9bcbf182-effc-ba9b-0df3-afac620ad152)

---------

Co-authored-by: open-swe[bot] <open-swe@users.noreply.github.com>
2026-06-22 22:15:29 -04:00

The agent engineering platform.

PyPI - License PyPI - Downloads Version Twitter / X

LangChain is a framework for building agents and 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.

Tip

Just getting started? Check out Deep Agents — a higher-level package built on LangChain for agents that have built-in capabilites for common usage patterns such as planning, subagents, file system usage, and more.

Quickstart

uv add langchain
from langchain.chat_models import init_chat_model

model = init_chat_model("openai:gpt-5.5")
result = model.invoke("Hello, world!")

If you're looking for more advanced customization or agent orchestration, check out LangGraph, our framework for building controllable agent workflows.

For an equivalent JS/TS library, check out LangChain.js.

Tip

For developing, debugging, and deploying AI agents and LLM applications, see LangSmith.

LangChain 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.

  • Deep Agents — Build agents that can plan, use subagents, and leverage file systems for complex tasks
  • LangGraph — Build agents that can reliably handle complex tasks with our low-level agent orchestration framework
  • Integrations — Chat & embedding models, tools & toolkits, and more
  • LangSmith — Agent evals, observability, and debugging for LLM apps
  • LangSmith Deployment — Deploy and scale agents with a purpose-built platform for long-running, stateful workflows

Why use LangChain?

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

  • Real-time data augmentation — Easily connect LLMs to diverse data sources and external/internal systems, drawing from LangChain's 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 application's needs. As the industry frontier evolves, adapt quickly — LangChain's abstractions keep you moving without losing momentum
  • Rapid prototyping — Quickly build and iterate on LLM applications with LangChain's modular, component-based architecture. Test different approaches and workflows without rebuilding from scratch, accelerating your development cycle
  • Production-ready features — Deploy reliable applications with built-in support for monitoring, evaluation, and debugging through integrations like LangSmith. Scale with confidence using battle-tested patterns and best practices
  • Vibrant community and ecosystem — Leverage a rich ecosystem of integrations, templates, and community-contributed components. Benefit from continuous improvements and stay up-to-date with the latest AI developments through an active open-source community
  • Flexible abstraction layers — Work at the level of abstraction that suits your needs — from high-level chains for quick starts to low-level components for fine-grained control. LangChain grows with your application's complexity

Resources

Description
Building applications with LLMs through composability
Readme MIT Cite this repository 4.9 GiB
Languages
Python 85.8%
omnetpp-msg 13.6%
Makefile 0.4%
Shell 0.1%