Bring Cloud Phone
to OpenAI Agents SDK
Learn how to connect JustCall to OpenAI Agents SDK 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 OpenAI Agents SDK?
The OpenAI Agents SDK auto-discovers all 12 tools from JustCall through native MCP integration. Build agents with built-in guardrails, tracing, and handoff patterns. chain multiple agents where one queries JustCall, another analyzes results, and a third generates reports, all orchestrated through Vinkius.
- —
Native MCP integration via
MCPServerSse, pass the URL and the SDK auto-discovers all tools with full type safety - —
Built-in guardrails, tracing, and handoff patterns let you build production-grade agents without reinventing safety infrastructure
- —
Lightweight and composable: chain multiple agents and MCP servers in a single pipeline with minimal boilerplate
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First-party OpenAI support ensures optimal compatibility with GPT models for tool calling and structured output
JustCall in OpenAI Agents SDK
JustCall and 4,000+ other MCP servers. One platform. One governance layer.
Teams that connect JustCall to OpenAI Agents SDK 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 OpenAI Agents SDK
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 OpenAI Agents SDK 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 OpenAI Agents SDK
Every tool call from OpenAI Agents SDK 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 the OpenAI Agents SDK connect to MCP?
Use MCPServerSse(url=...) to create a server connection. The SDK auto-discovers all tools and makes them available to your agent with full type information.
Can I use multiple MCP servers in one agent?
Yes. Pass a list of MCPServerSse instances to the agent constructor. The agent can use tools from all connected servers within a single run.
Does the SDK support streaming responses?
Yes. The SDK supports SSE and Streamable HTTP transports, both of which work natively with Vinkius.
MCPServerStreamableHttp not found
Ensure you have the latest version: pip install --upgrade openai-agents
Agent not calling tools
Make sure your prompt explicitly references the task the tools can help with.
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