# Connect LangChain to iMessage | Novu Connect

> Give your LangChain agent a voice in iMessage with Novu Connect.

Canonical: https://novu.co/channels/imessage/langchain/

Markdown: https://novu.co/channels/imessage/langchain.md

LangChain is the open-source framework for building agents and LLM apps in Python and JavaScript. Novu Connect gives it a voice in iMessage.

Novu Connect is the communication layer, the ACI, Agent Communication Infrastructure, bridge between your LangChain agent and iMessage. Your agent keeps running in your app. Novu delivers its messages to iMessage, maps each user, and forwards their replies back to your handler. We never run your agent's reasoning. That is the whole point.

Connect command: npx novu connect --channel sendblue --runtime langchain

## What is LangChain

LangChain gives developers the building blocks for agents: models, tools, memory, and control flow. You compose chains and agents, wire in your own tools, and keep the reasoning in your codebase. LangChain runs the agent. It does not carry the conversation to your users. That last mile, reaching a person in Slack and routing their reply back to your agent, is what Novu Connect adds.

- Tool calling and structured output for real agent actions
- Memory and retrieval for context across a conversation
- Runs in Python or JavaScript, in your own app
- A large ecosystem of integrations you already use

## How to connect LangChain to iMessage

1. Keep your LangChain agent: Your agent, tools, and memory stay in your codebase exactly as they are. Novu Connect wraps the input and output, so your LangChain logic does not change when you add iMessage.
2. Connect the channel: Run npx novu connect --channel sendblue --runtime langchain. The CLI scaffolds a bridge route in your app and connects iMessage. You can also paste the prompt below into your coding agent and let it wire the bridge for you.
3. Wire the bridge handler: The CLI prints a requirements file with the bridge route and handler. Point it at your LangChain agent so messages from iMessage reach your agent and its replies route back to the same conversation.
4. Go live: Sign in to keep the agent live, then run your dev server. Your LangChain agent now holds a two-way conversation in iMessage, and the same agent can reach every other channel from one thread.

Prompt for your coding agent: Connect this project's LangChain agent to iMessage with Novu using instructions from https://novu.co/agents.md

## LangChain and iMessage, common questions

### Do I have to rewrite my LangChain agent to add iMessage?

No. Novu Connect uses a custom-code bridge. Your LangChain agent keeps running in your app. Novu forwards messages from iMessage to your handler and routes replies back, so your agent code stays the same.

### Does Novu run my LangChain agent?

No. Novu Connect is the communication layer, the ACI, Agent Communication Infrastructure, bridge between your agent and iMessage. You own the reasoning and the tools. We never run your brain, that is the whole point.

### Is the conversation two-way, or just outbound messages?

Two-way. Novu Connect maps each iMessage user to your LangChain agent and forwards their replies back into the same conversation, with retries on delivery.

### How do I connect my AI agent to iMessage?

Run npx novu connect --channel sendblue, or paste the prompt above into your coding agent. You enter your Sendblue credentials in the CLI, and Novu Connect handles user identity and two-way routing so your agent code stays the same.

### How does iMessage delivery work?

Through Sendblue. Your users message a number from the Messages app, Novu routes each message to your agent with its conversation history, and replies come back into the same thread with live typing indicators.