JustCall MCP Server

The JustCall Model Context Protocol (MCP) Server lets Large Language Models (LLMs) and AI agents make real-world voice calls and send SMS directly through JustCall’s APIs — securely, contextually, and programmatically.

It provides a function-calling interface for conversational AI systems, enabling:

📞 AI-powered calling: Let your LLM initiate, manage, or transcribe calls using JustCall.
💬 Smart messaging: Allow your AI agent to send or respond to SMS within conversations.
⚙️ Seamless integration: Use the MCP standard to connect JustCall’s telephony capabilities with any LLM runtime or orchestration framework.

In short: It gives your LLMs a voice and a phone number — turning chatbots into truly conversational agents.

Claude Desktop Setup

Open Claude Desktop and press CMD + , to go to Settings.
Click on the Connectors tab.
Click on the Add Custom Connector button.
Add name as JustCall and Remote Server Url as https://mcp.justcall.host/mcp.
Now on JustCall from the Connectors list click on Connect button for JustCall.
It will open a JustCall page requesting API key and secret.
Get your JustCall API Key & Secret from the JustCall dashboard (https://app.justcall.io/app/developersApiCredentials).
Enter the API key and Secret and press Continue, it should redirect back you to Claude.

Claude Web - https://claude.ai

Open connectors url in your Browser - https://claude.ai/settings/connectors.
Click on the Connectors tab.
Click on the Add Custom Connector button.
Add name as JustCall and Remote Server Url as https://mcp.justcall.host/mcp.
Now on JustCall from the Connectors list click on Connect button for JustCall.
It will open a JustCall page requesting API key and secret.
Get your JustCall API Key & Secret from the JustCall dashboard (https://app.justcall.io/app/developersApiCredentials).
Enter the API key and Secret and press Continue, it should redirect back you to Claude.

Chat GPT (Only available on Plus, Pro, Business and Enterprise)

Open connectors url in your Browser - https://chatgpt.com/#settings/Connectors.
Click on the Apps & Connectors tab.
Ensure developer mode is enabled in advanced settings
Click on the Create button.
Add name as JustCall and MCP Server Url as https://mcp.justcall.host/mcp. You can skip other fields.
Now on JustCall from the Connectors list click on Connect button for JustCall.
It will open a JustCall page requesting API key and secret.
Get your JustCall API Key & Secret from the JustCall dashboard (https://app.justcall.io/app/developersApiCredentials).
Enter the API key and Secret and press Continue, it should redirect back you to Chat GPT.

Remote MCP

To connect to JustCall's MCP server remotely:

Streamable HTTP (Recommended)

The default and recommended way to connect is via Streamable HTTP Transport:

Connect to https://mcp.justcall.host/mcp from any MCP client using Streamable HTTP Transport
Include your JustCall API key as a bearer token in the request headers
Example header: Authorization: Bearer <JUSTCALL_API_KEY>:<JUSTCALL_API_SECRET>

Authentication & Security

The JustCall MCP Server implements OAuth2 authentication for secure access to all endpoints.

OAuth2 Configuration

The server supports OAuth2 authorization with the following features:

Authorization Endpoint: OAuth2 authorization server metadata is available at /.well-known/oauth-authorization-server
Grant Type: Authorization code flow with PKCE (Proof Key for Code Exchange)
Code Challenge Method: S256 (SHA-256)
Token Authentication: All MCP and SSE endpoints require Bearer token authentication

Protected Endpoints

The following endpoints require valid Bearer token authentication:

/mcp - Main MCP endpoint
/sse - Server-Sent Events endpoint
/sse/message - SSE message endpoint

Authentication Header Format

Include your JustCall API credentials as a Bearer token:

Code

Authorization: Bearer <JWT_TOKEN_BY_OAUTH>
Authorization: Bearer <JUSTCALL_API_KEY>:<JUSTCALL_API_SECRET>

Public Endpoints

The following endpoints are publicly accessible:

/health - Health check endpoint (returns 200 OK)
/.well-known/oauth-authorization-server - OAuth2 authorization server metadata

API Usage & Rate Limits

This MCP server uses the JustCall Developer API. All API requests are subject to the rate limits associated with your JustCall API key. Please refer to your JustCall API credentials configuration.

Available Tools

The JustCall MCP Server provides 66 tools organized into the following categories:

JustCall API Tools

📞 Calls (6 tools)

list_calls - Lists all JustCall calls with various filtering options
get_call - Get a specific JustCall call by ID
update_call - Update a JustCall call (disposition, notes, rating)
get_call_journey - Fetch the sequence of events for a specific call
get_voice_agent_data - Get voice agent data for a specific call (deprecated, use get_voice_agent_call)
get_voice_agent_call - Retrieve voice agent related data for a specific call

👥 Users & Agents (3 tools)

list_users - List all users/agents in the account
get_user - Get detailed information for a specific user/agent
update_user_availability - Update a user's availability status to available or unavailable for calls

💬 SMS & Messaging (11 tools)

send_sms - Send an SMS/text message to a contact
list_sms - Retrieve all SMS/text messages
get_sms - Get detailed information for a specific SMS/text message
check_sms_reply - Check for the most recent inbound SMS reply from a specific contact
list_sms_tags - Retrieve all SMS tags used for organizing text messages
get_sms_tag - Get detailed information for a specific SMS tag
create_sms_tag - Create a new tag for organizing SMS conversations
delete_sms_tag - Delete a specific SMS tag
list_sms_threads - Retrieve all SMS threads/conversations associated with a JustCall number
get_sms_thread - Retrieve a specific SMS thread/conversation by ID
add_sms_thread_tag - Add tag to an SMS thread/conversation

📇 Contacts (6 tools)

list_contacts - Retrieve all contacts from the CRM
get_contact - Retrieve detailed information for a specific contact by ID
create_contact - Create a new contact in the CRM
update_contact - Update/modify details of an existing contact
update_contact_status - Add or remove a contact from DND/DNM/Blacklist lists
add_contacts_blacklist - Add one or more contacts to the global blacklist in bulk

📊 Analytics (4 tools)

get_agent_analytics - Retrieve agent analytics data for specified date range
get_account_analytics - Retrieve account analytics data for specified date range
get_number_analytics - Retrieve number analytics data for specified date range
get_sales_dialer_analytics - Retrieve comprehensive analytics data for sales dialer campaigns

🔔 Webhooks (2 tools)

list_webhooks - Retrieve all configured webhooks
create_webhook - Create a new webhook endpoint to receive real-time notifications

📱 Phone Numbers (2 tools)

list_numbers - Retrieve all JustCall phone numbers
get_number - Retrieve detailed information for a specific JustCall phone number

👥 User Groups (2 tools)

list_user_groups - Retrieve all user groups defined in the account
get_user_group - Retrieve detailed information for a specific user group by ID

📅 Appointments (3 tools)

list_appointment_slots - Retrieve all available time slots for appointments on a specific calendar
create_appointment - Schedule a new appointment on a specific calendar
get_appointment - Retrieve details of a specific appointment by its ID

💚 WhatsApp (5 tools)

list_whatsapp_messages - Retrieve all WhatsApp messages associated with the account
get_whatsapp_message - Retrieve detailed information for a specific WhatsApp message by ID
send_whatsapp_message - Send a new WhatsApp message to a contact number
list_whatsapp_templates - Retrieve all WhatsApp message templates available in the account
check_whatsapp_message_reply - Check for the most recent inbound WhatsApp message from a contact

🤖 AI Analysis (4 tools)

list_calls_ai_analysis - Retrieve AI-generated analysis (transcription, summary, insights) for all calls
get_call_ai_analysis - Retrieve AI-generated analysis for a specific call by Call ID
list_meetings_ai_analysis - Retrieve AI-generated analysis for recorded meetings (Zoom, Google Meet)
get_meeting_ai_analysis - Retrieve AI-generated analysis for a specific meeting by Instance ID

🎙️ Voice Agents (2 tools)

list_voice_agents - Retrieve all AI voice agents associated with the account
create_voice_agent_call - Initiate an outbound call from a configured AI voice agent to a contact

Sales Dialer Tools

📢 Campaigns (6 tools)

list_campaigns - Retrieve all sales dialer campaigns
get_campaign - Retrieve detailed information for a specific sales dialer campaign
create_campaign - Create a new sales dialer campaign
update_campaign - Update campaign details including name, description, status, and assignments
list_salesdialer_campaign_contacts - Retrieve all contacts in a specific campaign
add_salesdialer_campaign_contact - Add contact to a specific campaign

👥 Contacts (8 tools)

list_salesdialer_contacts - Retrieve all contacts from Sales Dialer
get_salesdialer_contact - Retrieve detailed information for a specific contact by ID
create_salesdialer_contact - Create a new contact in Sales Dialer
update_salesdialer_contact - Update/modify details of an existing contact
import_salesdialer_contacts - Import multiple contacts into Sales Dialer or a campaign in bulk
import_salesdialer_contacts_status - Check the status of a bulk import job by batch ID
add_salesdialer_contacts_dnca - Add one or more contacts to the "Do Not Call Again" list in bulk
list_salesdialer_custom_fields - Fetch all custom contact fields defined in Sales Dialer

📞 Calls (2 tools)

list_salesdialer_calls - Retrieve all calls made via the Sales Dialer
get_salesdialer_call - Retrieve detailed information for a specific Sales Dialer call by ID

📊 Analytics (2 tools)

get_sales_dialer_analytics - Retrieve comprehensive analytics data for sales dialer campaigns
get_salesdialer_agent_analytics - Retrieve call performance analytics of a specific agent for a campaign.