JustCall MCP Server for Mastra AI 10 tools — connect in under 2 minutes
Mastra AI is a TypeScript-native agent framework built for modern web stacks. Connect JustCall through the Vinkius and Mastra agents discover all tools automatically — type-safe, streaming-ready, and deployable anywhere Node.js runs.
ASK AI ABOUT THIS MCP SERVER
Vinkius supports streamable HTTP and SSE.
import { Agent } from "@mastra/core/agent";
import { createMCPClient } from "@mastra/mcp";
import { openai } from "@ai-sdk/openai";
async function main() {
// Your Vinkius token — get it at cloud.vinkius.com
const mcpClient = await createMCPClient({
servers: {
"justcall": {
url: "https://edge.vinkius.com/[YOUR_TOKEN_HERE]/mcp",
},
},
});
const tools = await mcpClient.getTools();
const agent = new Agent({
name: "JustCall Agent",
instructions:
"You help users interact with JustCall " +
"using 10 tools.",
model: openai("gpt-4o"),
tools,
});
const result = await agent.generate(
"What can I do with JustCall?"
);
console.log(result.text);
}
main();
* Every MCP server runs on Vinkius-managed infrastructure inside AWS - a purpose-built runtime with per-request V8 isolates, Ed25519 signed audit chains, and sub-40ms cold starts optimized for native MCP execution. See our infrastructure
About JustCall MCP Server
Empower your AI agents with JustCall's cloud phone system. This MCP server allows you to list and retrieve phone calls, track SMS/MMS messages, manage contacts, and access call recordings directly through the JustCall API. Ideal for automating communication workflows and sales engagement.
Mastra's agent abstraction provides a clean separation between LLM logic and JustCall tool infrastructure. Connect 10 tools through the Vinkius and use Mastra's built-in workflow engine to chain tool calls with conditional logic, retries, and parallel execution — deployable to any Node.js host in one command.
The JustCall MCP Server exposes 10 tools through the Vinkius. Connect it to Mastra AI in under two minutes — no API keys to rotate, no infrastructure to provision, no vendor lock-in. Your configuration, your data, your control.
How to Connect JustCall to Mastra AI via MCP
Follow these steps to integrate the JustCall MCP Server with Mastra AI.
Install dependencies
Run npm install @mastra/core @mastra/mcp @ai-sdk/openai
Replace the token
Replace [YOUR_TOKEN_HERE] with your Vinkius token
Run the agent
Save to agent.ts and run with npx tsx agent.ts
Explore tools
Mastra discovers 10 tools from JustCall via MCP
Why Use Mastra AI with the JustCall MCP Server
Mastra AI provides unique advantages when paired with JustCall through the Model Context Protocol.
Mastra's agent abstraction provides a clean separation between LLM logic and tool infrastructure — add JustCall without touching business code
Built-in workflow engine chains MCP tool calls with conditional logic, retries, and parallel execution for complex automation
TypeScript-native: full type inference for every JustCall tool response with IDE autocomplete and compile-time checks
One-command deployment to any Node.js host — Vercel, Railway, Fly.io, or your own infrastructure
JustCall + Mastra AI Use Cases
Practical scenarios where Mastra AI combined with the JustCall MCP Server delivers measurable value.
Automated workflows: build multi-step agents that query JustCall, process results, and trigger downstream actions in a typed pipeline
SaaS integrations: embed JustCall as a first-class tool in your product's AI features with Mastra's clean agent API
Background jobs: schedule Mastra agents to query JustCall on a cron and store results in your database automatically
Multi-agent systems: create specialist agents that collaborate using JustCall tools alongside other MCP servers
JustCall MCP Tools for Mastra AI (10)
These 10 tools become available when you connect JustCall to Mastra AI via MCP:
get_call
Includes timestamps, participants, and associated notes. Use this for deep investigation of a specific communication event. Retrieves details for a specific call
get_contact
Returns associated phone numbers, email addresses, and metadata. Use this for detailed customer vetting before or after a call. Retrieves details for a specific contact
list_calls
Returns call direction (inbound/outbound), duration, status, and IDs. Use this to audit communication activity or track call volumes. Lists all phone calls
list_campaigns
g., dialer campaigns). Useful for monitoring sales outreach and telemarketing efforts. Lists all calling campaigns
list_contacts
Returns names, phone numbers, and IDs. Use this to search for customers or provide contact information to the user. Lists all contacts in JustCall
list_messages
Includes message content, sender/receiver, and delivery status. Essential for monitoring text-based customer interactions. Lists all SMS/MMS messages
list_numbers
Useful for identifying which numbers are available for specific campaigns or teams. Lists all phone numbers in your JustCall account
list_recordings
Use this when the user wants to audit call quality or retrieve a specific conversation record. Lists all call recordings
list_users
Useful for identifying which agent handled a specific call or message. Lists all users in your organization
list_webhooks
Useful for auditing system integrations. Lists all configured webhooks
Example Prompts for JustCall in Mastra AI
Ready-to-use prompts you can give your Mastra AI agent to start working with JustCall immediately.
"List all recent phone calls in JustCall."
"Show me the latest SMS messages."
"Check the details for contact ID '123'."
Troubleshooting JustCall MCP Server with Mastra AI
Common issues when connecting JustCall to Mastra AI through the Vinkius, and how to resolve them.
createMCPClient not exported
npm install @mastra/mcpJustCall + Mastra AI FAQ
Common questions about integrating JustCall MCP Server with Mastra AI.
How does Mastra AI connect to MCP servers?
MCPClient with the server URL and pass it to your agent. Mastra discovers all tools and makes them available with full TypeScript types.Can Mastra agents use tools from multiple servers?
Does Mastra support workflow orchestration?
Connect JustCall with your favorite client
Step-by-step setup guides for every MCP-compatible client and framework:
Anthropic's native desktop app for Claude with built-in MCP support.
AI-first code editor with integrated LLM-powered coding assistance.
GitHub Copilot in VS Code with Agent mode and MCP support.
Purpose-built IDE for agentic AI coding workflows.
Autonomous AI coding agent that runs inside VS Code.
Anthropic's agentic CLI for terminal-first development.
Python SDK for building production-grade OpenAI agent workflows.
Google's framework for building production AI agents.
Type-safe agent development for Python with first-class MCP support.
TypeScript toolkit for building AI-powered web applications.
TypeScript-native agent framework for modern web stacks.
Python framework for orchestrating collaborative AI agent crews.
Leading Python framework for composable LLM applications.
Data-aware AI agent framework for structured and unstructured sources.
Microsoft's framework for multi-agent collaborative conversations.
Connect JustCall to Mastra AI
Get your token, paste the configuration, and start using 10 tools in under 2 minutes. No API key management needed.