# Connect LangChain and LangGraph agents to a NZ phone number, SMS and email

**Short answer:** Install langchain[mcp] 1.4 or later, wrap a FastMCP Client pointed at https://agentline.nz/mcp with your Agentline NZ API key as auth in langchain.mcp.MCPAdapter, and pass adapter.list_tools() to create_agent. The agent can then text from a New Zealand 028 number, use an @agentline.nz inbox and wait for one-time codes.

## Before you start

- An Agentline NZ API key from Dashboard → API keys, exported as AGENTLINE_KEY. Start free with an email inbox (no card), or take a 7-day trial of Starter or Pro to get a number.
- Your 028 number is set up within a few days of signup. Your email inbox works straight away.

## Steps

1. **Install LangChain with MCP support.** langchain.mcp replaces the separate langchain-mcp-adapters package. If you have the old package, uninstall it.

   ```bash
   pip install "langchain[mcp]>=1.4.0"
   pip uninstall langchain-mcp-adapters
   ```

2. **Connect and build the agent.** A string passed as auth is sent as Authorization: Bearer, and an https URL selects Streamable HTTP.

   ```python
   import asyncio, os
   from fastmcp.client import Client
   from langchain.agents import create_agent
   from langchain.mcp import MCPAdapter

   async def main():
       client = Client("https://agentline.nz/mcp", auth=os.environ["AGENTLINE_KEY"])
       async with MCPAdapter(client) as adapter:
           tools = await adapter.list_tools()
           agent = create_agent("claude-sonnet-5", tools)
           result = await agent.ainvoke(
               {"messages": [{"role": "user", "content": "What's my Agentline NZ number?"}]}
           )
           print(result["messages"][-1].content)

   asyncio.run(main())
   ```

3. **Run it.** Run the script. The agent should call get_my_number.

## Good to know

- langchain.mcp is in beta and raises LangChainBetaWarning. It doesn't wrap MCP prompts or resources yet, but Agentline NZ only uses tools.
- LangGraph's create_react_agent is replaced by langchain.agents.create_agent, which runs on LangGraph.
- Use any chat model your LangChain install supports in create_agent.
- Standard NZ mobile numbers only (020–029). No landlines, short codes, premium or international numbers.

## FAQ

### Can I still use MultiServerMCPClient?

LangChain's migration guide replaces langchain-mcp-adapters and MultiServerMCPClient with langchain.mcp.MCPAdapter. Existing code with transport http and a headers entry keeps working until you migrate.

### What does Agentline NZ cost?

Starter is NZ$29/month and Pro is NZ$79/month, billed in NZ dollars. Start free with an email inbox (no card), or take a 7-day trial of Starter or Pro to get a number. Agentline NZ is not GST-registered, so no GST is charged.

### How long does it take to get the 028 number?

Your 028 number is set up within a few days of signup. Your email inbox works straight away. Full refund if your number hasn't arrived within 30 days of paying.

### Can my assistant send marketing or bulk texts?

No. Transactional and assistant messages only: replies, bookings, confirmations, reminders people asked for, and codes. Marketing, promotions, cold texts and bulk texts are blocked. See [What we don't allow](/what-we-dont-allow).

## Related

- [Connect the OpenAI Agents SDK to a NZ phone number, SMS and email](/integrations/openai-agents-sdk)
- [Connect CrewAI agents to a NZ phone number, SMS and email](/integrations/crewai)
- [How do I create an Agentline NZ API key?](/help/how-to-create-an-api-key)

[Start free](https://agentline.nz/signup) · Start free with an email inbox (no card), or take a 7-day trial of Starter or Pro to get a number.