LangChain

uv add langchain langchain-mcp-adapters langchain-openai

import os
import base64
from langchain_mcp_adapters import MultiServerMCPClient
from langchain.agents import AgentExecutor, create_tool_calling_agent
from langchain_openai import ChatOpenAI
from langchain.prompts import ChatPromptTemplate

# Configure StackOne account
STACKONE_ACCOUNT_ID = "<account_id>"  # Your StackOne account ID

# Encode API key for Basic auth
auth_token = base64.b64encode(
    f"{os.getenv('STACKONE_API_KEY')}:".encode()
).decode()

# Connect to StackOne MCP server
mcp_client = MultiServerMCPClient({
    "stackone": {
        "url": "https://api.stackone.com/mcp",
        "transport": "streamable_http",
        "headers": {
            "Authorization": f"Basic {auth_token}",
            "x-account-id": STACKONE_ACCOUNT_ID,
            "MCP-Protocol-Version": "2025-06-18"
        }
    }
})

# Get StackOne tools
tools = mcp_client.list_tools()

# Create agent with StackOne tools
llm = ChatOpenAI(model="gpt-5")
prompt = ChatPromptTemplate.from_messages([
    ("system", "You are a helpful assistant with access to data from connected platforms."),
    ("human", "{input}"),
    ("placeholder", "{agent_scratchpad}")
])

agent = create_tool_calling_agent(llm, tools, prompt)
agent_executor = AgentExecutor(agent=agent, tools=tools)

# Run agent
result = agent_executor.invoke({"input": "List Salesforce accounts"})
print(result["output"])

STACKONE_API_KEY=<stackone_api_key>
OPENAI_API_KEY=your_openai_key