Bring Cloud Phone
to Mastra AI
Learn how to connect JustCall to Mastra AI and start using 12 AI agent tools in minutes. Fully managed, enterprise secure, and ready to use without writing a single line of code.
GDPR Free for SubscribersCompatible with every major AI agent and IDE
Gemini
What is the JustCall MCP Server?
Connect your JustCall account to any AI agent and manage phone communications through natural conversation.
What you can do
- Call Management — Make outbound calls, track call logs with duration and status
- SMS Messaging — Send text messages to contacts and track delivery
- Contact Database — List contacts, create new entries, and inspect profiles
- Call Recordings — Access call recordings with metadata
- Phone Numbers — List available and assigned phone numbers
- Agent Monitoring — Track agent performance, call volumes, and availability
How it works
- Subscribe to this server
- Enter your JustCall API Key and API Secret
- Start managing calls from Claude, Cursor, or any MCP-compatible client
Who is this for?
- Sales Teams — make calls, send follow-up SMS, and track communication history
- Support Teams — manage call queues and monitor agent performance
- Operations — automate phone outreach and SMS campaigns
Built-in capabilities (12)
Create a new contact
Get my profile
Get call details
Get contact details
Get message details
List JustCall numbers
List phone calls
List phone contacts
List SMS/MMS messages
List team members
List active webhooks
Send SMS/MMS
Why Mastra AI?
Mastra's agent abstraction provides a clean separation between LLM logic and JustCall tool infrastructure. Connect 12 tools through 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.
- —
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 in Mastra AI
JustCall and 4,000+ other MCP servers. One platform. One governance layer.
Teams that connect JustCall to Mastra AI through Vinkius don't need to source, host, or maintain individual MCP servers. Every tool call runs inside a hardened runtime with credential isolation, DLP, and a signed audit chain.
Raw MCP | Vinkius | |
|---|---|---|
| Server catalog | Find and host yourself | 4,000+ managed |
| Infrastructure | Self-hosted | Sandboxed V8 isolates |
| Credential handling | Plaintext in config | Vault + runtime injection |
| Data loss prevention | None | Configurable DLP policies |
| Kill switch | None | Global instant shutdown |
| Financial circuit breakers | None | Per-server limits + alerts |
| Audit trail | None | Ed25519 signed logs |
| SIEM log streaming | None | Splunk, Datadog, Webhook |
| Honeytokens | None | Canary alerts on leak |
| Custom domains | Not applicable | DNS challenge verified |
| GDPR compliance | Manual effort | Automated purge + export |
Why teams choose Vinkius for JustCall in Mastra AI
The JustCall 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. All 12 tools execute in hardened sandboxes optimized for native MCP execution.
Your AI agents in Mastra AI only access the data you authorize, with DLP that blocks sensitive information from ever reaching the model, kill switch for instant shutdown, and up to 60% token savings. Enterprise-grade infrastructure, zero maintenance.
* 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
How Vinkius secures
JustCall for Mastra AI
Every tool call from Mastra AI to the JustCall MCP Server is protected by DLP redaction, cryptographic audit chains, V8 sandbox isolation, kill switch, and financial circuit breakers.
Frequently asked questions
Can I make calls and send SMS through the AI agent?
Yes. Make outbound calls with destination number and track status. Send SMS messages to any contact with delivery tracking. Use contact management tools to find recipient numbers.
Does JustCall require two credentials?
Yes. JustCall uses an API Key and API Secret pair for authentication. Both are sent as Bearer credentials against api.justcall.io/v1.
Can I listen to call recordings and track agent performance?
Yes. Access call recordings with duration and metadata. Monitor agent call volumes, average handle time, and availability status.
How does Mastra AI connect to MCP servers?
Create an 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?
Yes. Pass multiple MCP clients to the agent constructor. Mastra merges all tool schemas and the agent can call any tool from any server.
Does Mastra support workflow orchestration?
Yes. Mastra has a built-in workflow engine that lets you chain MCP tool calls with branching logic, error handling, and parallel execution.
createMCPClient not exported
Install: npm install @mastra/mcp
Explore More MCP Servers
View all →
Forecast
6 toolsManage AI-powered project resources via Forecast — track projects and tasks, handle team availability, and monitor milestones directly from any AI agent.
Knackly
8 toolsGenerate legal and business documents from smart templates with conditional logic that adapts content to every unique situation.
Weiban Assistant
10 toolsCustomer relationship management for WeCom — manage leads, customers, and group chats via AI.
Gigs
12 toolsManage mobile subscriptions, track data usage, and oversee eSIMs via AI agents with Gigs.