Source code for langchain.agents.openai_tools.base
from typing import Optional, Sequence
from langchain_core.language_models import BaseLanguageModel
from langchain_core.prompts.chat import ChatPromptTemplate
from langchain_core.runnables import Runnable, RunnablePassthrough
from langchain_core.tools import BaseTool
from langchain_core.utils.function_calling import convert_to_openai_tool
from langchain.agents.format_scratchpad.openai_tools import (
format_to_openai_tool_messages,
)
from langchain.agents.output_parsers.openai_tools import OpenAIToolsAgentOutputParser
[docs]def create_openai_tools_agent(
llm: BaseLanguageModel,
tools: Sequence[BaseTool],
prompt: ChatPromptTemplate,
strict: Optional[bool] = None,
) -> Runnable:
"""Create an agent that uses OpenAI tools.
Args:
llm: LLM to use as the agent.
tools: Tools this agent has access to.
prompt: The prompt to use. See Prompt section below for more on the expected
input variables.
Returns:
A Runnable sequence representing an agent. It takes as input all the same input
variables as the prompt passed in does. It returns as output either an
AgentAction or AgentFinish.
Raises:
ValueError: If the prompt is missing required variables.
Example:
.. code-block:: python
from langchain import hub
from langchain_community.chat_models import ChatOpenAI
from langchain.agents import AgentExecutor, create_openai_tools_agent
prompt = hub.pull("hwchase17/openai-tools-agent")
model = ChatOpenAI()
tools = ...
agent = create_openai_tools_agent(model, tools, prompt)
agent_executor = AgentExecutor(agent=agent, tools=tools)
agent_executor.invoke({"input": "hi"})
# Using with chat history
from langchain_core.messages import AIMessage, HumanMessage
agent_executor.invoke(
{
"input": "what's my name?",
"chat_history": [
HumanMessage(content="hi! my name is bob"),
AIMessage(content="Hello Bob! How can I assist you today?"),
],
}
)
Prompt:
The agent prompt must have an `agent_scratchpad` key that is a
``MessagesPlaceholder``. Intermediate agent actions and tool output
messages will be passed in here.
Here's an example:
.. code-block:: python
from langchain_core.prompts import ChatPromptTemplate, MessagesPlaceholder
prompt = ChatPromptTemplate.from_messages(
[
("system", "You are a helpful assistant"),
MessagesPlaceholder("chat_history", optional=True),
("human", "{input}"),
MessagesPlaceholder("agent_scratchpad"),
]
)
"""
missing_vars = {"agent_scratchpad"}.difference(
prompt.input_variables + list(prompt.partial_variables)
)
if missing_vars:
raise ValueError(f"Prompt missing required variables: {missing_vars}")
llm_with_tools = llm.bind(
tools=[convert_to_openai_tool(tool, strict=strict) for tool in tools]
)
agent = (
RunnablePassthrough.assign(
agent_scratchpad=lambda x: format_to_openai_tool_messages(
x["intermediate_steps"]
)
)
| prompt
| llm_with_tools
| OpenAIToolsAgentOutputParser()
)
return agent