langchain_google_vertexai.chains.create_structured_runnable(function: Union[Type[BaseModel], Sequence[Type[BaseModel]]], llm: Runnable, *, prompt: Optional[BasePromptTemplate] = None, use_extra_step: bool = False) Runnable[source]

Create a runnable sequence that uses OpenAI functions.

  • function (Union[Type[BaseModel], Sequence[Type[BaseModel]]]) – Either a single pydantic.BaseModel class or a sequence of pydantic.BaseModels classes. For best results, pydantic.BaseModels should have descriptions of the parameters.

  • llm (Runnable) – Language model to use, assumed to support the Google Vertex function-calling API.

  • prompt (Optional[BasePromptTemplate]) – BasePromptTemplate to pass to the model.

  • use_extra_step (bool) – whether to make an extra step to parse output into a function


A runnable sequence that will pass in the given functions to the model when run.

Return type



from typing import Optional

from langchain_google_vertexai import ChatVertexAI, create_structured_runnable
from langchain_core.prompts import ChatPromptTemplate
from langchain_core.pydantic_v1 import BaseModel, Field

class RecordPerson(BaseModel):
    """Record some identifying information about a person."""

    name: str = Field(..., description="The person's name")
    age: int = Field(..., description="The person's age")
    fav_food: Optional[str] = Field(None, description="The person's favorite food")

class RecordDog(BaseModel):
    """Record some identifying information about a dog."""

    name: str = Field(..., description="The dog's name")
    color: str = Field(..., description="The dog's color")
    fav_food: Optional[str] = Field(None, description="The dog's favorite food")

llm = ChatVertexAI(model_name="gemini-pro")
prompt = ChatPromptTemplate.from_template("""
You are a world class algorithm for recording entities.
Make calls to the relevant function to record the entities in the following input: {input}
Tip: Make sure to answer in the correct format"""
chain = create_structured_runnable([RecordPerson, RecordDog], llm, prompt=prompt)
chain.invoke({"input": "Harry was a chubby brown beagle who loved chicken"})
# -> RecordDog(name="Harry", color="brown", fav_food="chicken")

Examples using create_structured_runnable