0efc5d538e
The compat bridge produces InvalidToolCallBlock when tool-call JSON parse
fails, but ChatModelStream had no handler for it. The finish event was
silently ignored, the stale chunk stayed in _tool_call_chunks, and
_finish's sweep re-parsed (failed again), fell back to args={}, and
appended a valid-looking ToolCallBlock — so the protocol said "invalid"
while the assembled AIMessage said "valid with empty args". An agent layer
downstream could then dispatch the malformed call.
The finish handler now routes invalid_tool_call blocks into
_invalid_tool_calls_acc and deletes the stale chunk entry; _finish's sweep
emits InvalidToolCallBlock on JSON failure instead of an empty-args tool
call; _assemble_message passes invalid_tool_calls through to AIMessage.
🦜🍎️ LangChain Core
Looking for the JS/TS version? Check out LangChain.js.
To help you ship LangChain apps to production faster, check out LangSmith. LangSmith is a unified developer platform for building, testing, and monitoring LLM applications.
Quick Install
pip install langchain-core
🤔 What is this?
LangChain Core contains the base abstractions that power the LangChain ecosystem.
These abstractions are designed to be as modular and simple as possible.
The benefit of having these abstractions is that any provider can implement the required interface and then easily be used in the rest of the LangChain ecosystem.
⛰️ Why build on top of LangChain Core?
The LangChain ecosystem is built on top of langchain-core. Some of the benefits:
- Modularity: We've designed Core around abstractions that are independent of each other, and not tied to any specific model provider.
- Stability: We are committed to a stable versioning scheme, and will communicate any breaking changes with advance notice and version bumps.
- Battle-tested: Core components have the largest install base in the LLM ecosystem, and are used in production by many companies.
📖 Documentation
For full documentation, see the API reference. For conceptual guides, tutorials, and examples on using LangChain, see the LangChain Docs. You can also chat with the docs using Chat LangChain.
📕 Releases & Versioning
See our Releases and Versioning policies.
💁 Contributing
As an open-source project in a rapidly developing field, we are extremely open to contributions, whether it be in the form of a new feature, improved infrastructure, or better documentation.
For detailed information on how to contribute, see the Contributing Guide.