Files
wehub-resource-sync a7d6d88f6f
CI / changes (push) Has been cancelled
CI / cd libs/checkpoint (push) Has been cancelled
CI / cd libs/checkpoint-conformance (push) Has been cancelled
CI / cd libs/checkpoint-postgres (push) Has been cancelled
CI / cd libs/checkpoint-sqlite (push) Has been cancelled
CI / cd libs/cli (push) Has been cancelled
CI / cd libs/prebuilt (push) Has been cancelled
CI / cd libs/sdk-py (push) Has been cancelled
CI / cd libs/langgraph (push) Has been cancelled
CI / Check SDK methods matching (push) Has been cancelled
CI / Check CLI schema hasn't changed #3.13 (push) Has been cancelled
CI / CLI integration test (push) Has been cancelled
CI / sdk-py integration test (push) Has been cancelled
CI / CI Success (push) Has been cancelled
baseline / benchmark (push) Has been cancelled
Deploy Redirects to GitHub Pages / deploy (push) Has been cancelled
chore: import upstream snapshot with attribution
2026-07-13 12:37:18 +08:00

90 lines
2.7 KiB
Python

from collections.abc import Sequence
from typing import Annotated, Literal, TypedDict
from langchain_community.tools.tavily_search import TavilySearchResults
from langchain_core.messages import BaseMessage
from langchain_openai import ChatOpenAI
from langgraph.graph import END, StateGraph, add_messages
from langgraph.prebuilt import ToolNode
tools = [TavilySearchResults(max_results=1)]
model_oai = ChatOpenAI(temperature=0)
model_oai = model_oai.bind_tools(tools)
class AgentState(TypedDict):
messages: Annotated[Sequence[BaseMessage], add_messages]
# Define the function that determines whether to continue or not
def should_continue(state):
messages = state["messages"]
last_message = messages[-1]
# If there are no tool calls, then we finish
if not last_message.tool_calls:
return "end"
# Otherwise if there is, we continue
else:
return "continue"
# Define the function that calls the model
def call_model(state, config):
model = model_oai
messages = state["messages"]
response = model.invoke(messages)
# We return a list, because this will get added to the existing list
return {"messages": [response]}
# Define the function to execute tools
tool_node = ToolNode(tools)
class ContextSchema(TypedDict):
model: Literal["anthropic", "openai"]
# Define a new graph
workflow = StateGraph(AgentState, context_schema=ContextSchema)
# Define the two nodes we will cycle between
workflow.add_node("agent", call_model)
workflow.add_node("action", tool_node)
# Set the entrypoint as `agent`
# This means that this node is the first one called
workflow.set_entry_point("agent")
# We now add a conditional edge
workflow.add_conditional_edges(
# First, we define the start node. We use `agent`.
# This means these are the edges taken after the `agent` node is called.
"agent",
# Next, we pass in the function that will determine which node is called next.
should_continue,
# Finally we pass in a mapping.
# The keys are strings, and the values are other nodes.
# END is a special node marking that the graph should finish.
# What will happen is we will call `should_continue`, and then the output of that
# will be matched against the keys in this mapping.
# Based on which one it matches, that node will then be called.
{
# If `tools`, then we call the tool node.
"continue": "action",
# Otherwise we finish.
"end": END,
},
)
# We now add a normal edge from `tools` to `agent`.
# This means that after `tools` is called, `agent` node is called next.
workflow.add_edge("action", "agent")
# Finally, we compile it!
# This compiles it into a LangChain Runnable,
# meaning you can use it as you would any other runnable
graph = workflow.compile()