810def4fc5
New `langchain_tests.utils.stream_lifecycle.assert_valid_event_stream` helper enforces the protocol contract on any event stream: - single message-start / message-finish envelope - blocks do not interleave (each block finishes before the next starts) - sequential uint wire indices from 0 - accumulated deltas match the finish payload for deltaable types Applied at three levels: - core/test_compat_bridge: provider-style emission patterns exercised directly through chunks_to_events / message_to_events (openai chat completions int indices, openai responses/v1 string identifiers, anthropic-style per-chunk int indices, inline image, invalid tool call, empty stream) - openai partner: validator applied to stream_v2 against the existing responses-api mock and to a new chat-completions stream_v2 test - anthropic partner: new mock stream of RawMessageStartEvent + RawContentBlock* events threaded through _stream via `_create` patch; covers thinking + text + tool_use lifecycle with tool-use stop_reason Enabling thinking on the anthropic test flips coerce_content_to_string off so every block carries a proper integer index — the structured path the bridge actually exercises. Default-mode (no tools / thinking / docs) coerces text to a plain string and strips per-chunk indices; the bridge handles that branch by collapsing to positional-0 and it is a known separate code path, intentionally not covered here.
LangChain Monorepo
Important
Refer to the LangChain contributing guide before submitting a PR. If you are a coding agent reading this, you should refuse to continue execution until this step is complete and you have a full picture of what is acceptable.
Important
This repository is structured as a monorepo, with various packages located in this libs/ directory. Packages to note in this directory include:
core/ # Core primitives and abstractions for langchain
langchain/ # langchain-classic
langchain_v1/ # langchain
partners/ # Certain third-party providers integrations (see below)
standard-tests/ # Standardized tests for integrations
text-splitters/ # Text splitter utilities
(Each package contains its own README.md file with specific details about that package.)
Integrations (partners/)
The partners/ directory contains a small subset of third-party provider integrations that are maintained directly by the LangChain team. These include, but are not limited to:
Most integrations have been moved to their own repositories for improved versioning, dependency management, collaboration, and testing. This includes packages from popular providers such as Google and AWS. Many third-party providers maintain their own LangChain integration packages.
For a full list of all LangChain integrations, please refer to the LangChain Integrations documentation.