5a9b1ec2dc
Sweep classic deprecations so every removal lands on `2.0.0`, runtime warnings carry the auto-generated since/removal/alternative line, and replacements steer at `langchain.agents.create_agent` and `with_structured_output(...)` instead of pre-v1 LangGraph + `python.langchain.com` links. ## Changes - **Bump removal targets from `1.0` / `1.0.0` to `2.0.0`** across agents, chains, memory, retrievers, structured-output, vectorstore toolkits, and the `langchain_classic._api.module_import` shim — gives users a real runway now that v1 has shipped. - **Move bespoke `message=` strings onto `addendum=`** (or split into `alternative=` + `addendum=`). `warn_deprecated` skips the auto-generated since/removal/alternative line whenever `message=` is set, so the prior pattern silently dropped that info from the runtime `LangChainDeprecationWarning`. Matches the pattern already used in `HTMLHeaderTextSplitter.split_text_from_url`, which is updated for consistency. - **Repoint `alternative=` at v1 replacements**: chains/memory/agent toolkits → `langchain.agents.create_agent` (with checkpointer or retrieval-tool guidance in the addendum); `openai_functions` and `chains/structured_output` → `ChatModel.with_structured_output(...)`; `openapi` chains → `ChatModel.bind_tools(...)` + HTTP client. `ConversationChain` no longer points at `RunnableWithMessageHistory`. - **Refresh `AGENT_DEPRECATION_WARNING`** in `langchain_classic._api.deprecation` — drop stale LangGraph and `python.langchain.com` links in favor of `langchain.agents.create_agent` and the `docs.langchain.com/oss/python/migrate/langchain-v1` guide. Propagates to all 13 caller sites in `agents/`. - **Newly deprecate `langchain_classic.chat_models.init_chat_model` and `langchain_classic.embeddings.init_embeddings`** with the framing *"maintained in `langchain`; `langchain-classic` retains this entry point for import-compatibility only"*. The classic docstring examples and the warning admonition both point at `langchain.chat_models`. - **Improve `init_chat_model` docstrings** in both `langchain_v1` and the classic copy: clarify `provider:model` prefix vs. `model_provider=`, recommend pinned IDs over moving aliases, add the `upstage` provider row, and refresh examples to GA models (`gpt-5.5`, `claude-opus-4-7`). - **Standardize partner Anthropic deprecations**: replace `AnthropicLLM`'s `model_validator(raise_warning)` with `@deprecated(since="0.1.0", removal="2.0.0", alternative="ChatAnthropic")`, and pin the `ChatAnthropic` `output_format` runtime warning at `langchain-anthropic 2.0.0` instead of "a future version".
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.