base.py — langchain Source File

Source Code

"""VectorStore agent."""

from typing import Any

from langchain_core._api import deprecated
from langchain_core.callbacks.base import BaseCallbackManager
from langchain_core.language_models import BaseLanguageModel

from langchain_classic.agents.agent import AgentExecutor
from langchain_classic.agents.agent_toolkits.vectorstore.prompt import (
    PREFIX,
    ROUTER_PREFIX,
)
from langchain_classic.agents.agent_toolkits.vectorstore.toolkit import (
    VectorStoreRouterToolkit,
    VectorStoreToolkit,
)
from langchain_classic.agents.mrkl.base import ZeroShotAgent
from langchain_classic.chains.llm import LLMChain


@deprecated(
    since="0.2.13",
    removal="1.0",
    message=(
        "This function will continue to be supported, but it is recommended for new "
        "use cases to be built with LangGraph. LangGraph offers a more flexible and "
        "full-featured framework for building agents, including support for "
        "tool-calling, persistence of state, and human-in-the-loop workflows. "
        "See API reference for this function for a replacement implementation: "
        "https://api.python.langchain.com/en/latest/agents/langchain.agents.agent_toolkits.vectorstore.base.create_vectorstore_agent.html "  # noqa: E501
        "Read more here on how to create agents that query vector stores: "
        "https://python.langchain.com/docs/how_to/qa_chat_history_how_to/#agents"
    ),
)
def create_vectorstore_agent(
    llm: BaseLanguageModel,
    toolkit: VectorStoreToolkit,
    callback_manager: BaseCallbackManager | None = None,
    prefix: str = PREFIX,
    verbose: bool = False,  # noqa: FBT001,FBT002
    agent_executor_kwargs: dict[str, Any] | None = None,
    **kwargs: Any,
) -> AgentExecutor:
    """Construct a VectorStore agent from an LLM and tools.

    !!! note
        This class is deprecated. See below for a replacement that uses tool
        calling methods and LangGraph. Install LangGraph with:

        ```bash
        pip install -U langgraph
        ```

        ```python
        from langchain_core.tools import create_retriever_tool
        from langchain_core.vectorstores import InMemoryVectorStore
        from langchain_openai import ChatOpenAI, OpenAIEmbeddings
        from langgraph.prebuilt import create_react_agent

// ... (171 more lines)