# How to integrate Callerapi MCP with Mastra AI

```json
{
  "title": "How to integrate Callerapi MCP with Mastra AI",
  "toolkit": "Callerapi",
  "toolkit_slug": "callerapi",
  "framework": "Mastra AI",
  "framework_slug": "mastra-ai",
  "url": "https://composio.dev/toolkits/callerapi/framework/mastra-ai",
  "markdown_url": "https://composio.dev/toolkits/callerapi/framework/mastra-ai.md",
  "updated_at": "2026-05-12T10:04:49.906Z"
}
```

## Introduction

This guide walks you through connecting Callerapi to Mastra AI using the Composio tool router. By the end, you'll have a working Callerapi agent that can check if this phone number is flagged as spam, retrieve carrier and business info for a caller, show your callerapi credit usage this month through natural language commands.
This guide will help you understand how to give your Mastra AI agent real control over a Callerapi account through Composio's Callerapi MCP server.
Before we dive in, let's take a quick look at the key ideas and tools involved.

## Also integrate Callerapi with

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

## TL;DR

Here's what you'll learn:
- Set up your environment so Mastra, OpenAI, and Composio work together
- Create a Tool Router session in Composio that exposes Callerapi tools
- Connect Mastra's MCP client to the Composio generated MCP URL
- Fetch Callerapi tool definitions and attach them as a toolset
- Build a Mastra agent that can reason, call tools, and return structured results
- Run an interactive CLI where you can chat with your Callerapi agent

## What is Mastra AI?

Mastra AI is a TypeScript framework for building AI agents with tool support. It provides a clean API for creating agents that can use external services through MCP.
Key features include:
- MCP Client: Built-in support for Model Context Protocol servers
- Toolsets: Organize tools into logical groups
- Step Callbacks: Monitor and debug agent execution
- OpenAI Integration: Works with OpenAI models via @ai-sdk/openai

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

The Callerapi MCP server is an implementation of the Model Context Protocol that connects your AI agent and assistants like Claude, Cursor, etc directly to your Callerapi account. It provides structured and secure access to caller identification and reputation data, so your agent can perform actions like verifying phone numbers, checking caller reputation, retrieving business and carrier details, and monitoring account usage on your behalf.
- Detailed phone number lookup: Instantly retrieve information about any phone number, including reputation, business association, carrier, and FTC complaints.
- Reputation and fraud assessment: Empower your agent to check if a phone number might be flagged for spam, robocalls, or fraud, helping you screen and validate callers.
- Business and carrier identification: Have your agent fetch in-depth business and carrier details for a given number to strengthen trust and context in communications.
- HLR (Home Location Register) checks: Enable your agent to request HLR data for deeper carrier and number status insights, including ported or roaming status.
- Account usage monitoring: Let your agent access your Callerapi user profile to monitor credit usage, monthly allocations, and remaining balance, keeping you informed about your API consumption.

## Supported Tools

| Tool slug | Name | Description |
|---|---|---|
| `CALLERAPI_DISPATCH_REPORTS_MANUALLY` | Dispatch Reports Manually | Tool to manually trigger today's spam reports webhook delivery for enterprise clients. Use when an immediate webhook dispatch of spam complaint reports is needed. This endpoint is restricted to enterprise accounts only. |
| `CALLERAPI_GET_PHONE_NUMBER_INFORMATION` | Get Phone Number Information | Tool to retrieve detailed information about a specific phone number, including reputation, business and carrier details, and FTC complaints. Use when the number is in E.164 format and set hlr=true to include HLR data (adds 1-3 seconds to response). |
| `CALLERAPI_GET_USER_INFORMATION` | Get User Information | Tool to retrieve information about the authenticated user, including email and credit usage details. Use after authentication to fetch current credits spent, monthly allocation, and credits left. |
| `CALLERAPI_LIST_WEBHOOK_SUBSCRIPTIONS` | List Webhook Subscriptions | Tool to list all webhook subscriptions for daily spam reports. Enterprise clients only. Use to retrieve all configured webhook endpoints that receive spam complaint notifications. |
| `CALLERAPI_SUBSCRIBE_DAILY_REPORTS` | Subscribe to Daily Spam Reports | Tool to subscribe to daily spam report webhooks for enterprise clients. Instead of polling, receive webhook deliveries with spam complaint data daily. Use when you want to set up automated daily reports for spam complaints. |
| `CALLERAPI_TEST_WEBHOOK` | Test Webhook | Tool to send a sample webhook payload to test your webhook endpoint integration. Use to validate webhook signature verification and endpoint configuration. Enterprise clients only. |
| `CALLERAPI_UNSUBSCRIBE_DAILY_REPORTS` | Unsubscribe from Daily Reports | Tool to unsubscribe from daily spam report webhooks. Use when you need to stop receiving daily reports at a specific webhook URL. Enterprise clients only. |

## Supported Triggers

None listed.

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

The Callerapi MCP server is an implementation of the Model Context Protocol that connects your AI agent to Callerapi. It provides structured and secure access so your agent can perform Callerapi 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 starting, make sure you have:
- Node.js 18 or higher
- A Composio account with an active API key
- An OpenAI API key
- Basic familiarity with TypeScript

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

OpenAI API Key
- Go to the [OpenAI dashboard](https://platform.openai.com/settings/organization/api-keys) and create an API key.
- You need credits or a connected billing setup to use the models.
- Store the key somewhere safe.
Composio API Key
- Log in to the [Composio dashboard](https://dashboard.composio.dev?utm_source=toolkits&utm_medium=framework_docs).
- Go to Settings and copy your API key.
- This key lets your Mastra agent talk to Composio and reach Callerapi through MCP.

### 2. Install dependencies

Install the required packages.
What's happening:
- @composio/core is the Composio SDK for creating MCP sessions
- @mastra/core provides the Agent class
- @mastra/mcp is Mastra's MCP client
- @ai-sdk/openai is the model wrapper for OpenAI
- dotenv loads environment variables from .env
```bash
npm install @composio/core @mastra/core @mastra/mcp @ai-sdk/openai dotenv
```

### 3. Set up environment variables

Create a .env file in your project root.
What's happening:
- COMPOSIO_API_KEY authenticates your requests to Composio
- COMPOSIO_USER_ID tells Composio which user this session belongs to
- OPENAI_API_KEY lets the Mastra agent call OpenAI models
```bash
COMPOSIO_API_KEY=your_composio_api_key_here
COMPOSIO_USER_ID=your_user_id_here
OPENAI_API_KEY=your_openai_api_key_here
```

### 4. Import libraries and validate environment

What's happening:
- dotenv/config auto loads your .env so process.env.* is available
- openai gives you a Mastra compatible model wrapper
- Agent is the Mastra agent that will call tools and produce answers
- MCPClient connects Mastra to your Composio MCP server
- Composio is used to create a Tool Router session
```typescript
import "dotenv/config";
import { openai } from "@ai-sdk/openai";
import { Agent } from "@mastra/core/agent";
import { MCPClient } from "@mastra/mcp";
import { Composio } from "@composio/core";
import * as readline from "readline";

import type { AiMessageType } from "@mastra/core/agent";

const openaiAPIKey = process.env.OPENAI_API_KEY;
const composioAPIKey = process.env.COMPOSIO_API_KEY;
const composioUserID = process.env.COMPOSIO_USER_ID;

if (!openaiAPIKey) throw new Error("OPENAI_API_KEY is not set");
if (!composioAPIKey) throw new Error("COMPOSIO_API_KEY is not set");
if (!composioUserID) throw new Error("COMPOSIO_USER_ID is not set");

const composio = new Composio({
  apiKey: composioAPIKey as string,
});
```

### 5. Create a Tool Router session for Callerapi

What's happening:
- create spins up a short-lived MCP HTTP endpoint for this user
- The toolkits array contains "callerapi" for Callerapi access
- session.mcp.url is the MCP URL that Mastra's MCPClient will connect to
```typescript
async function main() {
  const session = await composio.create(
    composioUserID as string,
    {
      toolkits: ["callerapi"],
    },
  );

  const composioMCPUrl = session.mcp.url;
  console.log("Callerapi MCP URL:", composioMCPUrl);
```

### 6. Configure Mastra MCP client and fetch tools

What's happening:
- MCPClient takes an id for this client and a list of MCP servers
- The headers property includes the x-api-key for authentication
- getTools fetches the tool definitions exposed by the Callerapi toolkit
```typescript
const mcpClient = new MCPClient({
    id: composioUserID as string,
    servers: {
      nasdaq: {
        url: new URL(composioMCPUrl),
        requestInit: {
          headers: session.mcp.headers,
        },
      },
    },
    timeout: 30_000,
  });

console.log("Fetching MCP tools from Composio...");
const composioTools = await mcpClient.getTools();
console.log("Number of tools:", Object.keys(composioTools).length);
```

### 7. Create the Mastra agent

What's happening:
- Agent is the core Mastra agent
- name is just an identifier for logging and debugging
- instructions guide the agent to use tools instead of only answering in natural language
- model uses openai("gpt-5") to configure the underlying LLM
```typescript
const agent = new Agent({
    name: "callerapi-mastra-agent",
    instructions: "You are an AI agent with Callerapi tools via Composio.",
    model: "openai/gpt-5",
  });
```

### 8. Set up interactive chat interface

What's happening:
- messages keeps the full conversation history in Mastra's expected format
- agent.generate runs the agent with conversation history and Callerapi toolsets
- maxSteps limits how many tool calls the agent can take in a single run
- onStepFinish is a hook that prints intermediate steps for debugging
```typescript
let messages: AiMessageType[] = [];

console.log("Chat started! Type 'exit' or 'quit' to end.\n");

const rl = readline.createInterface({
  input: process.stdin,
  output: process.stdout,
  prompt: "> ",
});

rl.prompt();

rl.on("line", async (userInput: string) => {
  const trimmedInput = userInput.trim();

  if (["exit", "quit", "bye"].includes(trimmedInput.toLowerCase())) {
    console.log("\nGoodbye!");
    rl.close();
    process.exit(0);
  }

  if (!trimmedInput) {
    rl.prompt();
    return;
  }

  messages.push({
    id: crypto.randomUUID(),
    role: "user",
    content: trimmedInput,
  });

  console.log("\nAgent is thinking...\n");

  try {
    const response = await agent.generate(messages, {
      toolsets: {
        callerapi: composioTools,
      },
      maxSteps: 8,
    });

    const { text } = response;

    if (text && text.trim().length > 0) {
      console.log(`Agent: ${text}\n`);
        messages.push({
          id: crypto.randomUUID(),
          role: "assistant",
          content: text,
        });
      }
    } catch (error) {
      console.error("\nError:", error);
    }

    rl.prompt();
  });

  rl.on("close", async () => {
    console.log("\nSession ended.");
    await mcpClient.disconnect();
    process.exit(0);
  });
}

main().catch((err) => {
  console.error("Fatal error:", err);
  process.exit(1);
});
```

## Complete Code

```typescript
import "dotenv/config";
import { openai } from "@ai-sdk/openai";
import { Agent } from "@mastra/core/agent";
import { MCPClient } from "@mastra/mcp";
import { Composio } from "@composio/core";
import * as readline from "readline";

import type { AiMessageType } from "@mastra/core/agent";

const openaiAPIKey = process.env.OPENAI_API_KEY;
const composioAPIKey = process.env.COMPOSIO_API_KEY;
const composioUserID = process.env.COMPOSIO_USER_ID;

if (!openaiAPIKey) throw new Error("OPENAI_API_KEY is not set");
if (!composioAPIKey) throw new Error("COMPOSIO_API_KEY is not set");
if (!composioUserID) throw new Error("COMPOSIO_USER_ID is not set");

const composio = new Composio({ apiKey: composioAPIKey as string });

async function main() {
  const session = await composio.create(composioUserID as string, {
    toolkits: ["callerapi"],
  });

  const composioMCPUrl = session.mcp.url;

  const mcpClient = new MCPClient({
    id: composioUserID as string,
    servers: {
      callerapi: {
        url: new URL(composioMCPUrl),
        requestInit: {
          headers: session.mcp.headers,
        },
      },
    },
    timeout: 30_000,
  });

  const composioTools = await mcpClient.getTools();

  const agent = new Agent({
    name: "callerapi-mastra-agent",
    instructions: "You are an AI agent with Callerapi tools via Composio.",
    model: "openai/gpt-5",
  });

  let messages: AiMessageType[] = [];

  const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout,
    prompt: "> ",
  });

  rl.prompt();

  rl.on("line", async (input: string) => {
    const trimmed = input.trim();
    if (["exit", "quit"].includes(trimmed.toLowerCase())) {
      rl.close();
      return;
    }

    messages.push({ id: crypto.randomUUID(), role: "user", content: trimmed });

    const { text } = await agent.generate(messages, {
      toolsets: { callerapi: composioTools },
      maxSteps: 8,
    });

    if (text) {
      console.log(`Agent: ${text}\n`);
      messages.push({ id: crypto.randomUUID(), role: "assistant", content: text });
    }

    rl.prompt();
  });

  rl.on("close", async () => {
    await mcpClient.disconnect();
    process.exit(0);
  });
}

main();
```

## Conclusion

You've built a Mastra AI agent that can interact with Callerapi through Composio's Tool Router.
You can extend this further by:
- Adding other toolkits like Gmail, Slack, or GitHub
- Building a web-based chat interface around this agent
- Using multiple MCP endpoints to enable cross-app workflows

## How to build Callerapi MCP Agent with another framework

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

## Related Toolkits

- [Aeroleads](https://composio.dev/toolkits/aeroleads) - Aeroleads is a B2B lead generation platform for finding business emails and phone numbers. Grow your sales pipeline faster with powerful prospecting tools.
- [Autobound](https://composio.dev/toolkits/autobound) - Autobound is an AI-powered sales engagement platform that crafts hyper-personalized outreach and insights. It helps sales teams boost response rates and close more deals through tailored content and recommendations.
- [Better proposals](https://composio.dev/toolkits/better_proposals) - Better Proposals is a web-based tool for crafting and sending professional proposals. It helps teams impress clients and close deals faster with slick, easy-to-use templates.
- [Bidsketch](https://composio.dev/toolkits/bidsketch) - Bidsketch is a proposal software that helps businesses create professional proposals quickly and efficiently. It streamlines the proposal process, saving time while boosting client win rates.
- [Bolna](https://composio.dev/toolkits/bolna) - Bolna is an AI platform for building conversational voice agents. It helps businesses automate support and streamline interactions through natural, voice-powered conversations.
- [Botsonic](https://composio.dev/toolkits/botsonic) - Botsonic is a no-code AI chatbot builder for easily creating and deploying chatbots to your website. It empowers businesses to offer conversational experiences without writing code.
- [Botstar](https://composio.dev/toolkits/botstar) - BotStar is a comprehensive chatbot platform for designing, developing, and training chatbots visually on Messenger and websites. It helps businesses automate conversations and customer interactions without coding.
- [Callingly](https://composio.dev/toolkits/callingly) - Callingly is a lead response management platform that automates immediate call and text follow-ups with new leads. It helps sales teams boost response speed and close more deals by connecting seamlessly with CRMs and lead sources.
- [Callpage](https://composio.dev/toolkits/callpage) - Callpage is a lead capture platform that lets businesses instantly connect with website visitors via callback. It boosts lead generation and increases your sales conversion rates.
- [Clearout](https://composio.dev/toolkits/clearout) - Clearout is an AI-powered service for verifying, finding, and enriching email addresses. It boosts deliverability and helps you discover high-quality leads effortlessly.
- [Clientary](https://composio.dev/toolkits/clientary) - Clientary is a platform for managing clients, invoices, projects, proposals, and more. It streamlines client work and saves you serious admin time.
- [Convolo ai](https://composio.dev/toolkits/convolo_ai) - Convolo ai is an AI-powered communications platform for sales teams. It accelerates lead response and improves conversion rates by automating calls and integrating workflows.
- [Delighted](https://composio.dev/toolkits/delighted) - Delighted is a customer feedback platform based on the Net Promoter System®. It helps you quickly gather, track, and act on customer sentiment.
- [Docsbot ai](https://composio.dev/toolkits/docsbot_ai) - Docsbot ai is a platform that lets you build custom AI chatbots trained on your documentation. It automates customer support and content generation, saving time and improving response quality.
- [Emelia](https://composio.dev/toolkits/emelia) - Emelia is an all-in-one B2B prospecting platform for cold-email, LinkedIn outreach, and prospect research. It streamlines outbound campaigns so you can find, engage, and warm up leads faster.
- [Findymail](https://composio.dev/toolkits/findymail) - Findymail is a B2B data provider offering verified email and phone contacts for sales prospecting. Enhance outreach with automated exports, email verification, and CRM enrichment.
- [Freshdesk](https://composio.dev/toolkits/freshdesk) - Freshdesk is customer support software with ticketing and automation tools. It helps teams streamline helpdesk operations for faster, better customer support.
- [Fullenrich](https://composio.dev/toolkits/fullenrich) - FullEnrich is a B2B contact enrichment platform that aggregates emails and phone numbers from 15+ data vendors. Instantly find and verify lead contact data to boost your outreach.
- [Gatherup](https://composio.dev/toolkits/gatherup) - GatherUp is a customer feedback and online review management platform. It helps businesses boost their reputation by streamlining how they collect and manage customer feedback.
- [Getprospect](https://composio.dev/toolkits/getprospect) - Getprospect is a business email discovery tool with LinkedIn integration. Use it to quickly find and verify professional email addresses.

## Frequently Asked Questions

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

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

### Can I use Tool Router MCP with Mastra AI?

Yes, you can. Mastra AI 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 Callerapi tools.

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

Yes, absolutely. You can configure which Callerapi 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 Callerapi data and credentials are handled as safely as possible.

---
[See all toolkits](https://composio.dev/toolkits) · [Composio docs](https://docs.composio.dev/llms.txt)
