# How to integrate Smtp2go MCP with LlamaIndex

```json
{
  "title": "How to integrate Smtp2go MCP with LlamaIndex",
  "toolkit": "Smtp2go",
  "toolkit_slug": "smtp2go",
  "framework": "LlamaIndex",
  "framework_slug": "llama-index",
  "url": "https://composio.dev/toolkits/smtp2go/framework/llama-index",
  "markdown_url": "https://composio.dev/toolkits/smtp2go/framework/llama-index.md",
  "updated_at": "2026-05-06T08:29:13.142Z"
}
```

## Introduction

This guide walks you through connecting Smtp2go to LlamaIndex using the Composio tool router. By the end, you'll have a working Smtp2go agent that can search for bounced emails this week, add marketing@mydomain.com as allowed sender, list all verified sender domains through natural language commands.
This guide will help you understand how to give your LlamaIndex agent real control over a Smtp2go account through Composio's Smtp2go MCP server.
Before we dive in, let's take a quick look at the key ideas and tools involved.

## Also integrate Smtp2go with

- [OpenAI Agents SDK](https://composio.dev/toolkits/smtp2go/framework/open-ai-agents-sdk)
- [Claude Agent SDK](https://composio.dev/toolkits/smtp2go/framework/claude-agents-sdk)
- [Claude Code](https://composio.dev/toolkits/smtp2go/framework/claude-code)
- [Claude Cowork](https://composio.dev/toolkits/smtp2go/framework/claude-cowork)
- [Codex](https://composio.dev/toolkits/smtp2go/framework/codex)
- [OpenClaw](https://composio.dev/toolkits/smtp2go/framework/openclaw)
- [Hermes](https://composio.dev/toolkits/smtp2go/framework/hermes-agent)
- [CLI](https://composio.dev/toolkits/smtp2go/framework/cli)
- [Google ADK](https://composio.dev/toolkits/smtp2go/framework/google-adk)
- [LangChain](https://composio.dev/toolkits/smtp2go/framework/langchain)
- [Vercel AI SDK](https://composio.dev/toolkits/smtp2go/framework/ai-sdk)
- [Mastra AI](https://composio.dev/toolkits/smtp2go/framework/mastra-ai)
- [CrewAI](https://composio.dev/toolkits/smtp2go/framework/crew-ai)

## TL;DR

Here's what you'll learn:
- Set your OpenAI and Composio API keys
- Install LlamaIndex and Composio packages
- Create a Composio Tool Router session for Smtp2go
- Connect LlamaIndex to the Smtp2go MCP server
- Build a Smtp2go-powered agent using LlamaIndex
- Interact with Smtp2go through natural language

## What is LlamaIndex?

LlamaIndex is a data framework for building LLM applications. It provides tools for connecting LLMs to external data sources and services through agents and tools.
Key features include:
- ReAct Agent: Reasoning and acting pattern for tool-using agents
- MCP Tools: Native support for Model Context Protocol
- Context Management: Maintain conversation context across interactions
- Async Support: Built for async/await patterns

## What is the Smtp2go MCP server, and what's possible with it?

The Smtp2go MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Smtp2go account. It provides structured and secure access to your email sending and management infrastructure, so your agent can perform actions like searching email activity, managing allowed senders, updating sender domains, and controlling IP allow lists on your behalf.
- Comprehensive email activity search: Ask your agent to filter and retrieve email events such as sends, opens, clicks, and bounces by recipient, date, or message ID.
- Allowed sender management: Have your agent add, update, remove, or view allowed sender email addresses to control who can send emails from your account.
- Sender domain configuration: Let the agent register new sender domains for SPF/DKIM verification and manage domain-related settings seamlessly.
- IP allow list control: Direct your agent to add or remove IP addresses or CIDR ranges in your account’s IP allow list, enhancing security for sending sources.
- Email delivery monitoring: Enable your agent to search and analyze sent emails, helping you monitor delivery, troubleshoot issues, and ensure reliable communication.

## Supported Tools

| Tool slug | Name | Description |
|---|---|---|
| `SMTP2GO_ACTIVITY_SEARCH` | Search Email Activity | Tool to search activity events like sends, opens, clicks, and bounces. use when you need to filter account email activity by date, event, recipient, or message id. |
| `SMTP2GO_ALLOWED_SENDERS_ADD` | Add Allowed Sender | Tool to add a new allowed sender email address. use when you need to whitelist a sender before sending email. example: add "user@example.com" to allowed senders list. |
| `SMTP2GO_ALLOWED_SENDERS_REMOVE` | Remove Allowed Sender | Tool to remove a sender email address from the allowed senders list. use when you need to revoke send permissions for a validated address. |
| `SMTP2GO_ALLOWED_SENDERS_UPDATE` | Update Allowed Sender | Tool to update details of an existing allowed sender. use after confirming the allowed sender id. |
| `SMTP2GO_ALLOWED_SENDERS_VIEW` | View Allowed Senders | Tool to view the list of allowed senders configured in your account. use after setting up smtp2go authentication to retrieve your allowed-senders list. example: 'show me all verified allowed senders.' |
| `SMTP2GO_DOMAIN_ADD` | Add Sender Domain | Tool to add a new sender domain for spf/dkim verification. use when you need to register a domain and optionally set tracking/return-path subdomains. |
| `SMTP2GO_EMAIL_SEARCH` | Search SMTP2GO Emails | Tool to search sent emails. use when filtering your smtp2go account's email activity by criteria like date, sender, or recipient. call after authentication. |
| `SMTP2GO_IP_ALLOW_LIST_ADD` | Add IP Allow List | Tool to add an ip address or cidr range to your account’s ip allow list. use when you need to whitelist specific sending sources by ip or cidr after confirming accuracy. |
| `SMTP2GO_IP_ALLOW_LIST_REMOVE` | Remove IP from Allow List | Tool to remove an ip address from your account's ip allow list. use after identifying the ip you wish to revoke. |
| `SMTP2GO_IP_ALLOW_LIST_VIEW` | View IP Allow List | Tool to view the list of ip addresses in your ip allow list. use after confirming your smtp2go api key is set. |
| `SMTP2GO_SMS_VIEW_RECEIVED` | View Received SMS | Tool to retrieve received sms replies for your smtp2go account. use when you need to fetch incoming sms messages for analysis or display. pagination supported via limit and offset. |
| `SMTP2GO_STATS_EMAIL_BOUNCES` | Get Email Bounces Stats | Tool to retrieve email bounces statistics. use after sending emails to analyze bounce metrics over a time period. |
| `SMTP2GO_STATS_EMAIL_CYCLE` | Email Cycle Statistics | Tool to retrieve email cycle statistics. use when you need to analyze email delivery metrics over a specified date range. |
| `SMTP2GO_STATS_EMAIL_HISTORY` | Email History Statistics | Tool to retrieve email history statistics. use when you need detailed delivery metrics within a date range. |
| `SMTP2GO_STATS_EMAIL_SPAM` | Email Spam Statistics | Tool to retrieve email spam report statistics. use when analyzing spam trends for sent emails. |
| `SMTP2GO_STATS_EMAIL_UNSUBS` | Email Unsubscription Stats | Tool to retrieve email unsubscribe statistics. use when you need unsubscribe data for your account over a date range. |
| `SMTP2GO_SUBACCOUNTS_SEARCH` | Search Subaccounts | Tool to search subaccounts. use after authenticating to filter and paginate your subaccounts by name, email, or status. |
| `SMTP2GO_SUBACCOUNTS_USAGE` | Subaccounts Usage | Tool to retrieve usage statistics for subaccounts. use when you need to monitor per-subaccount email usage. |
| `SMTP2GO_SUPPRESSION_ADD` | Add to Suppression List | Tool to add email addresses or domains to the suppression list. use when you need to block sending emails to specific recipients or entire domains after unsubscribes or bounces. |
| `SMTP2GO_SUPPRESSION_REMOVE` | Remove suppression entry | Tool to remove an email address or domain from the suppression list. use when you want to resume sending to the address or domain. |
| `SMTP2GO_SUPPRESSION_VIEW` | View Suppression List | Tool to view the suppression list. use when you need to inspect suppressed email addresses in your account. |
| `SMTP2GO_TEMPLATE_EDIT` | Edit Email Template | Tool to edit details of an existing email template. use when you need to update template properties after confirming its id. |
| `SMTP2GO_TEMPLATE_SEARCH` | Search Email Templates | Tool to search your collection of email templates by id or name. use when you need to find templates matching specific criteria after authentication. |
| `SMTP2GO_TEMPLATE_VIEW` | View Email Template | Tool to view details of a specific email template. use after you have the template id to inspect. |
| `SMTP2GO_USERS_SMTP_ADD` | Add SMTP User | Tool to add a new smtp user. use when you need to provision a fresh smtp credential after collecting username and password. |
| `SMTP2GO_USERS_SMTP_EDIT` | Edit SMTP User | Tool to edit details of an existing smtp user. use when you need to update username, password, sender restrictions, or enable/disable a user after confirming the target username. |
| `SMTP2GO_USERS_SMTP_REMOVE` | Remove SMTP User | Tool to remove an smtp user from your account. use when you need to revoke smtp access for a user. |
| `SMTP2GO_USERS_SMTP_VIEW` | View SMTP Users | Tool to list all smtp users configured on your account. use when you need to retrieve smtp user configurations. |
| `SMTP2GO_WEBHOOK_ADD` | Add Webhook | Tool to create a new webhook. use when you need real-time notifications of email or sms events. |
| `SMTP2GO_WEBHOOK_EDIT` | Edit Webhook | Tool to edit an existing webhook’s settings. use when you need to update a webhook's configuration after creation. |
| `SMTP2GO_WEBHOOK_REMOVE` | Remove webhook | Tool to remove a webhook. use when you want to delete a webhook by its id from your smtp2go account. |
| `SMTP2GO_WEBHOOK_VIEW` | View Webhooks | Tool to view all webhooks configured in your account. use when you need to inspect existing webhook configurations after setup. |

## Supported Triggers

None listed.

## Creating MCP Server - Stand-alone vs Composio SDK

The Smtp2go MCP server is an implementation of the Model Context Protocol that connects your AI agent to Smtp2go. It provides structured and secure access so your agent can perform Smtp2go operations on your behalf through a secure, permission-based interface.
With Composio's managed implementation, you don't have to create your own developer app. For production, if you're building an end product, we recommend using your own credentials. The managed server helps you prototype fast and go from 0-1 faster.

## Step-by-step Guide

### 1. Prerequisites

Before you begin, make sure you have:
- Python 3.8/Node 16 or higher installed
- A Composio account with the API key
- An OpenAI API key
- A Smtp2go account and project
- Basic familiarity with async Python/Typescript

### 1. Getting API Keys for OpenAI, Composio, and Smtp2go

No description provided.

### 2. Installing dependencies

No description provided.
```python
pip install composio-llamaindex llama-index llama-index-llms-openai llama-index-tools-mcp python-dotenv
```

```typescript
npm install @composio/llamaindex @llamaindex/openai @llamaindex/tools @llamaindex/workflow dotenv
```

### 3. Set environment variables

Create a .env file in your project root:
These credentials will be used to:
- Authenticate with OpenAI's GPT-5 model
- Connect to Composio's Tool Router
- Identify your Composio user session for Smtp2go access
```bash
OPENAI_API_KEY=your-openai-api-key
COMPOSIO_API_KEY=your-composio-api-key
COMPOSIO_USER_ID=your-user-id
```

### 4. Import modules

No description provided.
```python
import asyncio
import os
import dotenv

from composio import Composio
from composio_llamaindex import LlamaIndexProvider
from llama_index.core.agent.workflow import ReActAgent
from llama_index.core.workflow import Context
from llama_index.llms.openai import OpenAI
from llama_index.tools.mcp import BasicMCPClient, McpToolSpec

dotenv.load_dotenv()
```

```typescript
import "dotenv/config";
import readline from "node:readline/promises";
import { stdin as input, stdout as output } from "node:process";

import { Composio } from "@composio/core";

import { mcp } from "@llamaindex/tools";
import { agent as createAgent } from "@llamaindex/workflow";
import { openai } from "@llamaindex/openai";

dotenv.config();
```

### 5. Load environment variables and initialize Composio

No description provided.
```python
OPENAI_API_KEY = os.getenv("OPENAI_API_KEY")
COMPOSIO_API_KEY = os.getenv("COMPOSIO_API_KEY")
COMPOSIO_USER_ID = os.getenv("COMPOSIO_USER_ID")

if not OPENAI_API_KEY:
    raise ValueError("OPENAI_API_KEY is not set in the environment")
if not COMPOSIO_API_KEY:
    raise ValueError("COMPOSIO_API_KEY is not set in the environment")
if not COMPOSIO_USER_ID:
    raise ValueError("COMPOSIO_USER_ID is not set in the environment")
```

```typescript
const OPENAI_API_KEY = process.env.OPENAI_API_KEY;
const COMPOSIO_API_KEY = process.env.COMPOSIO_API_KEY;
const COMPOSIO_USER_ID = process.env.COMPOSIO_USER_ID;

if (!OPENAI_API_KEY) throw new Error("OPENAI_API_KEY is not set");
if (!COMPOSIO_API_KEY) throw new Error("COMPOSIO_API_KEY is not set");
if (!COMPOSIO_USER_ID) throw new Error("COMPOSIO_USER_ID is not set");
```

### 6. Create a Tool Router session and build the agent function

What's happening here:
- We create a Composio client using your API key and configure it with the LlamaIndex provider
- We then create a tool router MCP session for your user, specifying the toolkits we want to use (in this case, smtp2go)
- The session returns an MCP HTTP endpoint URL that acts as a gateway to all your configured tools
- LlamaIndex will connect to this endpoint to dynamically discover and use the available Smtp2go tools.
- The MCP tools are mapped to LlamaIndex-compatible tools and plug them into the Agent.
```python
async def build_agent() -> ReActAgent:
    composio_client = Composio(
        api_key=COMPOSIO_API_KEY,
        provider=LlamaIndexProvider(),
    )

    session = composio_client.create(
        user_id=COMPOSIO_USER_ID,
        toolkits=["smtp2go"],
    )

    mcp_url = session.mcp.url
    print(f"Composio MCP URL: {mcp_url}")

    mcp_client = BasicMCPClient(mcp_url, headers={"x-api-key": COMPOSIO_API_KEY})
    mcp_tool_spec = McpToolSpec(client=mcp_client)
    tools = await mcp_tool_spec.to_tool_list_async()

    llm = OpenAI(model="gpt-5")

    description = "An agent that uses Composio Tool Router MCP tools to perform Smtp2go actions."
    system_prompt = """
    You are a helpful assistant connected to Composio Tool Router.
    Use the available tools to answer user queries and perform Smtp2go actions.
    """
    return ReActAgent(tools=tools, llm=llm, description=description, system_prompt=system_prompt, verbose=True)
```

```typescript
async function buildAgent() {

  console.log(`Initializing Composio client...${COMPOSIO_USER_ID!}...`);
  console.log(`COMPOSIO_USER_ID: ${COMPOSIO_USER_ID!}...`);

  const composio = new Composio({
    apiKey: COMPOSIO_API_KEY,
    provider: new LlamaindexProvider(),
  });

  const session = await composio.create(
    COMPOSIO_USER_ID!,
    {
      toolkits: ["smtp2go"],
    },
  );

  const mcpUrl = session.mcp.url;
  console.log(`Composio Tool Router MCP URL: ${mcpUrl}`);

  const server = mcp({
    url: mcpUrl,
    clientName: "composio_tool_router_with_llamaindex",
    requestInit: {
      headers: {
        "x-api-key": COMPOSIO_API_KEY!,
      },
    },
    // verbose: true,
  });

  const tools = await server.tools();

  const llm = openai({ apiKey: OPENAI_API_KEY, model: "gpt-5" });

  const agent = createAgent({
    name: "composio_tool_router_with_llamaindex",
        description : "An agent that uses Composio Tool Router MCP tools to perform actions.",
    systemPrompt:
      "You are a helpful assistant connected to Composio Tool Router."+
"Use the available tools to answer user queries and perform Smtp2go actions." ,
    llm,
    tools,
  });

  return agent;
}
```

### 7. Create an interactive chat loop

No description provided.
```python
async def chat_loop(agent: ReActAgent) -> None:
    ctx = Context(agent)
    print("Type 'quit', 'exit', or Ctrl+C to stop.")

    while True:
        try:
            user_input = input("\nYou: ").strip()
        except (KeyboardInterrupt, EOFError):
            print("\nBye!")
            break

        if not user_input or user_input.lower() in {"quit", "exit"}:
            print("Bye!")
            break

        try:
            print("Agent: ", end="", flush=True)
            handler = agent.run(user_input, ctx=ctx)

            async for event in handler.stream_events():
                # Stream token-by-token from LLM responses
                if hasattr(event, "delta") and event.delta:
                    print(event.delta, end="", flush=True)
                # Show tool calls as they happen
                elif hasattr(event, "tool_name"):
                    print(f"\n[Using tool: {event.tool_name}]", flush=True)

            # Get final response
            response = await handler
            print()  # Newline after streaming
        except KeyboardInterrupt:
            print("\n[Interrupted]")
            continue
        except Exception as e:
            print(f"\nError: {e}")
```

```typescript
async function chatLoop(agent: ReturnType<typeof createAgent>) {
  const rl = readline.createInterface({ input, output });

  console.log("Type 'quit' or 'exit' to stop.");

  while (true) {
    let userInput: string;

    try {
      userInput = (await rl.question("\nYou: ")).trim();
    } catch {
      console.log("\nAgent: Bye!");
      break;
    }

    if (!userInput) {
      continue;
    }

    const lower = userInput.toLowerCase();
    if (lower === "quit" || lower === "exit") {
      console.log("Agent: Bye!");
      break;
    }

    try {
      process.stdout.write("Agent: ");

      const stream = agent.runStream(userInput);
      let finalResult: any = null;

      for await (const event of stream) {
        // The event.data contains the streamed content
        const data: any = event.data;

        // Check for streaming delta content
        if (data?.delta) {
          process.stdout.write(data.delta);
        }

        // Store final result for fallback
        if (data?.result || data?.message) {
          finalResult = data;
        }
      }

      // If no streaming happened, show the final result
      if (finalResult) {
        const answer =
          finalResult.result ??
          finalResult.message?.content ??
          finalResult.message ??
          "";
        if (answer && typeof answer === "string" && !answer.includes("[object")) {
          process.stdout.write(answer);
        }
      }

      console.log(); // New line after streaming completes
    } catch (err: any) {
      console.error("\nAgent error:", err?.message ?? err);
    }
  }

  rl.close();
}
```

### 8. Define the main entry point

What's happening here:
- We're orchestrating the entire application flow
- The agent gets built with proper error handling
- Then we kick off the interactive chat loop so you can start talking to Smtp2go
```python
async def main() -> None:
    agent = await build_agent()
    await chat_loop(agent)

if __name__ == "__main__":
    # Handle Ctrl+C gracefully
    signal.signal(signal.SIGINT, lambda s, f: (print("\nBye!"), exit(0)))
    try:
        asyncio.run(main())
    except KeyboardInterrupt:
        print("\nBye!")
```

```typescript
async function main() {
  try {
    const agent = await buildAgent();
    await chatLoop(agent);
  } catch (err) {
    console.error("Failed to start agent:", err);
    process.exit(1);
  }
}

main();
```

### 9. Run the agent

When prompted, authenticate and authorise your agent with Smtp2go, then start asking questions.
```bash
python llamaindex_agent.py
```

```typescript
npx ts-node llamaindex-agent.ts
```

## Complete Code

```python
import asyncio
import os
import signal
import dotenv

from composio import Composio
from composio_llamaindex import LlamaIndexProvider
from llama_index.core.agent.workflow import ReActAgent
from llama_index.core.workflow import Context
from llama_index.llms.openai import OpenAI
from llama_index.tools.mcp import BasicMCPClient, McpToolSpec

dotenv.load_dotenv()

OPENAI_API_KEY = os.getenv("OPENAI_API_KEY")
COMPOSIO_API_KEY = os.getenv("COMPOSIO_API_KEY")
COMPOSIO_USER_ID = os.getenv("COMPOSIO_USER_ID")

if not OPENAI_API_KEY:
    raise ValueError("OPENAI_API_KEY is not set")
if not COMPOSIO_API_KEY:
    raise ValueError("COMPOSIO_API_KEY is not set")
if not COMPOSIO_USER_ID:
    raise ValueError("COMPOSIO_USER_ID is not set")

async def build_agent() -> ReActAgent:
    composio_client = Composio(
        api_key=COMPOSIO_API_KEY,
        provider=LlamaIndexProvider(),
    )

    session = composio_client.create(
        user_id=COMPOSIO_USER_ID,
        toolkits=["smtp2go"],
    )

    mcp_url = session.mcp.url
    print(f"Composio MCP URL: {mcp_url}")

    mcp_client = BasicMCPClient(mcp_url, headers={"x-api-key": COMPOSIO_API_KEY})
    mcp_tool_spec = McpToolSpec(client=mcp_client)
    tools = await mcp_tool_spec.to_tool_list_async()

    llm = OpenAI(model="gpt-5")
    description = "An agent that uses Composio Tool Router MCP tools to perform Smtp2go actions."
    system_prompt = """
    You are a helpful assistant connected to Composio Tool Router.
    Use the available tools to answer user queries and perform Smtp2go actions.
    """
    return ReActAgent(
        tools=tools,
        llm=llm,
        description=description,
        system_prompt=system_prompt,
        verbose=True,
    );

async def chat_loop(agent: ReActAgent) -> None:
    ctx = Context(agent)
    print("Type 'quit', 'exit', or Ctrl+C to stop.")

    while True:
        try:
            user_input = input("\nYou: ").strip()
        except (KeyboardInterrupt, EOFError):
            print("\nBye!")
            break

        if not user_input or user_input.lower() in {"quit", "exit"}:
            print("Bye!")
            break

        try:
            print("Agent: ", end="", flush=True)
            handler = agent.run(user_input, ctx=ctx)

            async for event in handler.stream_events():
                # Stream token-by-token from LLM responses
                if hasattr(event, "delta") and event.delta:
                    print(event.delta, end="", flush=True)
                # Show tool calls as they happen
                elif hasattr(event, "tool_name"):
                    print(f"\n[Using tool: {event.tool_name}]", flush=True)

            # Get final response
            response = await handler
            print()  # Newline after streaming
        except KeyboardInterrupt:
            print("\n[Interrupted]")
            continue
        except Exception as e:
            print(f"\nError: {e}")

async def main() -> None:
    agent = await build_agent()
    await chat_loop(agent)

if __name__ == "__main__":
    # Handle Ctrl+C gracefully
    signal.signal(signal.SIGINT, lambda s, f: (print("\nBye!"), exit(0)))
    try:
        asyncio.run(main())
    except KeyboardInterrupt:
        print("\nBye!")
```

```typescript
import "dotenv/config";
import readline from "node:readline/promises";
import { stdin as input, stdout as output } from "node:process";

import { Composio } from "@composio/core";
import { LlamaindexProvider } from "@composio/llamaindex";

import { mcp } from "@llamaindex/tools";
import { agent as createAgent } from "@llamaindex/workflow";
import { openai } from "@llamaindex/openai";

dotenv.config();

const OPENAI_API_KEY = process.env.OPENAI_API_KEY;
const COMPOSIO_API_KEY = process.env.COMPOSIO_API_KEY;
const COMPOSIO_USER_ID = process.env.COMPOSIO_USER_ID;

if (!OPENAI_API_KEY) {
    throw new Error("OPENAI_API_KEY is not set in the environment");
  }
if (!COMPOSIO_API_KEY) {
    throw new Error("COMPOSIO_API_KEY is not set in the environment");
  }
if (!COMPOSIO_USER_ID) {
    throw new Error("COMPOSIO_USER_ID is not set in the environment");
  }

async function buildAgent() {

  console.log(`Initializing Composio client...${COMPOSIO_USER_ID!}...`);
  console.log(`COMPOSIO_USER_ID: ${COMPOSIO_USER_ID!}...`);

  const composio = new Composio({
    apiKey: COMPOSIO_API_KEY,
    provider: new LlamaindexProvider(),
  });

  const session = await composio.create(
    COMPOSIO_USER_ID!,
    {
      toolkits: ["smtp2go"],
    },
  );

  const mcpUrl = session.mcp.url;
  console.log(`Composio Tool Router MCP URL: ${mcpUrl}`);

  const server = mcp({
    url: mcpUrl,
    clientName: "composio_tool_router_with_llamaindex",
    requestInit: {
      headers: {
        "x-api-key": COMPOSIO_API_KEY!,
      },
    },
    // verbose: true,
  });

  const tools = await server.tools();

  const llm = openai({ apiKey: OPENAI_API_KEY, model: "gpt-5" });

  const agent = createAgent({
    name: "composio_tool_router_with_llamaindex",
    description:
      "An agent that uses Composio Tool Router MCP tools to perform actions.",
    systemPrompt:
      "You are a helpful assistant connected to Composio Tool Router."+
"Use the available tools to answer user queries and perform Smtp2go actions." ,
    llm,
    tools,
  });

  return agent;
}

async function chatLoop(agent: ReturnType<typeof createAgent>) {
  const rl = readline.createInterface({ input, output });

  console.log("Type 'quit' or 'exit' to stop.");

  while (true) {
    let userInput: string;

    try {
      userInput = (await rl.question("\nYou: ")).trim();
    } catch {
      console.log("\nAgent: Bye!");
      break;
    }

    if (!userInput) {
      continue;
    }

    const lower = userInput.toLowerCase();
    if (lower === "quit" || lower === "exit") {
      console.log("Agent: Bye!");
      break;
    }

    try {
      process.stdout.write("Agent: ");

      const stream = agent.runStream(userInput);
      let finalResult: any = null;

      for await (const event of stream) {
        // The event.data contains the streamed content
        const data: any = event.data;

        // Check for streaming delta content
        if (data?.delta) {
          process.stdout.write(data.delta);
        }

        // Store final result for fallback
        if (data?.result || data?.message) {
          finalResult = data;
        }
      }

      // If no streaming happened, show the final result
      if (finalResult) {
        const answer =
          finalResult.result ??
          finalResult.message?.content ??
          finalResult.message ??
          "";
        if (answer && typeof answer === "string" && !answer.includes("[object")) {
          process.stdout.write(answer);
        }
      }

      console.log(); // New line after streaming completes
    } catch (err: any) {
      console.error("\nAgent error:", err?.message ?? err);
    }
  }

  rl.close();
}

async function main() {
  try {
    const agent = await buildAgent();
    await chatLoop(agent);
  } catch (err: any) {
    console.error("Failed to start agent:", err?.message ?? err);
    process.exit(1);
  }
}

main();
```

## Conclusion

You've successfully connected Smtp2go to LlamaIndex through Composio's Tool Router MCP layer.
Key takeaways:
- Tool Router dynamically exposes Smtp2go tools through an MCP endpoint
- LlamaIndex's ReActAgent handles reasoning and orchestration; Composio handles integrations
- The agent becomes more capable without increasing prompt size
- Async Python provides clean, efficient execution of agent workflows
You can easily extend this to other toolkits like Gmail, Notion, Stripe, GitHub, and more by adding them to the toolkits parameter.

## How to build Smtp2go MCP Agent with another framework

- [OpenAI Agents SDK](https://composio.dev/toolkits/smtp2go/framework/open-ai-agents-sdk)
- [Claude Agent SDK](https://composio.dev/toolkits/smtp2go/framework/claude-agents-sdk)
- [Claude Code](https://composio.dev/toolkits/smtp2go/framework/claude-code)
- [Claude Cowork](https://composio.dev/toolkits/smtp2go/framework/claude-cowork)
- [Codex](https://composio.dev/toolkits/smtp2go/framework/codex)
- [OpenClaw](https://composio.dev/toolkits/smtp2go/framework/openclaw)
- [Hermes](https://composio.dev/toolkits/smtp2go/framework/hermes-agent)
- [CLI](https://composio.dev/toolkits/smtp2go/framework/cli)
- [Google ADK](https://composio.dev/toolkits/smtp2go/framework/google-adk)
- [LangChain](https://composio.dev/toolkits/smtp2go/framework/langchain)
- [Vercel AI SDK](https://composio.dev/toolkits/smtp2go/framework/ai-sdk)
- [Mastra AI](https://composio.dev/toolkits/smtp2go/framework/mastra-ai)
- [CrewAI](https://composio.dev/toolkits/smtp2go/framework/crew-ai)

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- [Bouncer](https://composio.dev/toolkits/bouncer) - Bouncer is an email validation platform that verifies the authenticity of email addresses in real-time and batch. It helps boost deliverability and reduce bounce rates for your communications.
- [Conveyor](https://composio.dev/toolkits/conveyor) - Conveyor is a platform that automates security reviews with a Trust Center and AI-driven questionnaire automation. It streamlines compliance and vendor security processes for faster, hassle-free reviews.
- [Crowdin](https://composio.dev/toolkits/crowdin) - Crowdin is a localization management platform that streamlines translation workflows and collaboration. It helps teams centralize multilingual content, boost productivity, and automate translation processes.
- [Databox](https://composio.dev/toolkits/databox) - Databox is a business analytics platform that connects your data from any tool and device. It helps you track KPIs, build dashboards, and discover actionable insights.
- [Detrack](https://composio.dev/toolkits/detrack) - Detrack is a delivery management platform for real-time tracking and proof of delivery. It helps businesses automate notifications and keep customers updated every step of the way.
- [Dnsfilter](https://composio.dev/toolkits/dnsfilter) - Dnsfilter is a cloud-based DNS security and content filtering solution. It helps organizations block online threats and manage safe internet access with ease.
- [Faraday](https://composio.dev/toolkits/faraday) - Faraday lets you embed AI in workflows across your stack for smarter automation. It boosts your favorite tools with actionable intelligence and seamless integration.
- [Feathery](https://composio.dev/toolkits/feathery) - Feathery is an AI-powered platform for building dynamic data intake forms with advanced logic. It helps teams automate complex workflows and collect structured data with ease.
- [Fillout forms](https://composio.dev/toolkits/fillout_forms) - Fillout forms is an online platform for building and managing forms with a flexible API. It lets you create, distribute, and collect responses from forms with ease.
- [Formdesk](https://composio.dev/toolkits/formdesk) - Formdesk is an online form builder for creating and managing professional forms. It's perfect for collecting data, automating workflows, and integrating form submissions with your favorite services.
- [Formsite](https://composio.dev/toolkits/formsite) - Formsite lets you build online forms and surveys with drag-and-drop simplicity. Capture, manage, and integrate form responses securely for streamlined workflows.
- [Graphhopper](https://composio.dev/toolkits/graphhopper) - GraphHopper is an enterprise-grade Directions API for routing, optimization, and geocoding across multiple vehicle types. It enables fast, reliable route planning and logistics automation for businesses.
- [Hyperbrowser](https://composio.dev/toolkits/hyperbrowser) - Hyperbrowser is a next-generation platform for scalable browser automation. It empowers AI agents to interact with web apps, automate workflows, and handle browser sessions at scale.
- [La Growth Machine](https://composio.dev/toolkits/lagrowthmachine) - La Growth Machine automates multi-channel sales outreach and routine tasks for sales teams. Streamline your workflow and focus on closing more deals.
- [Leverly](https://composio.dev/toolkits/leverly) - Leverly is a workflow automation platform that connects and coordinates actions across your apps. It streamlines repetitive processes so your business runs smoother, faster, and with fewer manual steps.
- [Maintainx](https://composio.dev/toolkits/maintainx) - Maintainx is a cloud-based CMMS for centralizing maintenance data, communication, and workflows. It helps organizations streamline maintenance operations and improve team coordination.
- [Make](https://composio.dev/toolkits/make) - Make is an automation platform that connects your favorite apps and services. Build powerful, custom workflows without writing code.
- [Ntfy](https://composio.dev/toolkits/ntfy) - Ntfy is a notification service to send push messages to phones or desktops. Instantly deliver alerts and updates to users, devices, or teams.

## Frequently Asked Questions

### What are the differences in Tool Router MCP and Smtp2go MCP?

With a standalone Smtp2go MCP server, the agents and LLMs can only access a fixed set of Smtp2go tools tied to that server. However, with the Composio Tool Router, agents can dynamically load tools from Smtp2go and many other apps based on the task at hand, all through a single MCP endpoint.

### Can I use Tool Router MCP with LlamaIndex?

Yes, you can. LlamaIndex fully supports MCP integration. You get structured tool calling, message history handling, and model orchestration while Tool Router takes care of discovering and serving the right Smtp2go tools.

### Can I manage the permissions and scopes for Smtp2go while using Tool Router?

Yes, absolutely. You can configure which Smtp2go scopes and actions are allowed when connecting your account to Composio. You can also bring your own OAuth credentials or API configuration so you keep full control over what the agent can do.

### How safe is my data with Composio Tool Router?

All sensitive data such as tokens, keys, and configuration is fully encrypted at rest and in transit. Composio is SOC 2 Type 2 compliant and follows strict security practices so your Smtp2go data and credentials are handled as safely as possible.

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