Vapi MCP connector

1. Install the SDK

   Node.js

   npm install @scalekit-sdk/node

   Python

   pip install scalekit

   Full SDK reference: Node.js | Python

2. Set your credentials

   Add your Scalekit credentials to your .env file. Find values in app.scalekit.com > Developers > API Credentials.

   .env

   SCALEKIT_ENVIRONMENT_URL=<your-environment-url>
   SCALEKIT_CLIENT_ID=<your-client-id>
   SCALEKIT_CLIENT_SECRET=<your-client-secret>

3. Set up the connector

   Register your Vapi MCP credentials with Scalekit so it can authenticate requests on your behalf. You do this once per environment.

   Dashboard setup steps

   Register your Vapi API key with Scalekit so it can authenticate and proxy requests to the Vapi MCP server on behalf of your users. Vapi MCP uses bearer token authentication — there is no redirect URI or OAuth flow. Scalekit sends the key as Authorization: Bearer <token> to the Vapi MCP endpoint at https://mcp.vapi.ai/mcp.

   1. Get a Vapi API key

      • Go to dashboard.vapi.ai/org/api-keys and sign in or create an account.

      • Under API Keys, copy your Private Key. Use the private key — it authorizes server-side calls to the Vapi API.

      • Treat this key as a secret. Anyone with it can manage your assistants, calls, and phone numbers.

   2. Create a connection in Scalekit

      • In the Scalekit dashboard, go to AgentKit > Connections. Find Vapi MCP and click Create.

      • Note the Connection name — you use this as connection_name in your code (for example, vapimcp).

   3. Add a connected account

      Connected accounts link a specific user identifier in your system to a Vapi API key. Add them via the dashboard for testing, or via the Scalekit API in production.

      Via dashboard (for testing)

      • Open the connection you created and click the Connected Accounts tab → Add account.

      • Fill in:

        • Your User’s ID — a unique identifier for this user in your system (for example, user_123)
        • Vapi API key — the private key you copied in step 1

      • Click Save.

      Via API (for production)

      Node.js

      await scalekit.actions.upsertConnectedAccount({
        connectionName: 'vapimcp',
        identifier: 'user_123',       // your user's unique ID
        // Security: never hard-code the API key — read it from a secret store or env var.
        credentials: { token: process.env.VAPI_API_KEY },
      });

      Python

      scalekit_client.actions.upsert_connected_account(
          connection_name="vapimcp",
          identifier="user_123",
          # Security: never hard-code the API key — read it from a secret store or env var.
          credentials={"token": os.environ["VAPI_API_KEY"]},
      )

4. Make your first call

   Node.js

   quickstart.ts

   import { ScalekitClient } from '@scalekit-sdk/node'
   import 'dotenv/config'
   
   const scalekit = new ScalekitClient(
     process.env.SCALEKIT_ENV_URL,
     process.env.SCALEKIT_CLIENT_ID,
     process.env.SCALEKIT_CLIENT_SECRET,
   )
   const actions = scalekit.actions
   
   const connector = 'vapimcp'
   const identifier = 'user_123'
   
   // Make your first call
   const result = await actions.executeTool({
     connector,
     identifier,
     toolName: 'vapimcp_list_assistants',
     toolInput: { rationale: 'YOUR_RATIONALE' },
   })
   console.log(result)

   Python

   quickstart.py

   import os
   from scalekit.client import ScalekitClient
   from dotenv import load_dotenv
   load_dotenv()
   
   scalekit_client = ScalekitClient(
       env_url=os.getenv("SCALEKIT_ENV_URL"),
       client_id=os.getenv("SCALEKIT_CLIENT_ID"),
       client_secret=os.getenv("SCALEKIT_CLIENT_SECRET"),
   )
   actions = scalekit_client.actions
   
   connection_name = "vapimcp"
   identifier = "user_123"
   
   # Make your first call
   result = actions.execute_tool(
       tool_input={"rationale":"YOUR_RATIONALE"},
       tool_name="vapimcp_list_assistants",
       connection_name=connection_name,
       identifier=identifier,
   )
   print(result)

What you can do

Connect this agent connector to let your agent:

• Update tool, assistant — Updates an existing Vapi tool’s configuration
• List tools, phone numbers, calls — Lists all Vapi tools configured in the account
• Get tool, phone number, call — Retrieves the full configuration of a specific Vapi tool by ID, including its type (SMS, transfer call, function, or API request) and associated settings
• Create tool, call, assistant — Creates a new Vapi tool that can be attached to assistants

Common workflows

Tool calling

• Use vapimcp_list_assistants to discover existing assistants, then vapimcp_get_assistant to read a specific assistant’s full configuration before changing it.
• Use vapimcp_create_assistant to provision a new voice AI assistant, and vapimcp_update_assistant to change only the fields you pass — omitted fields keep their current values.
• Use vapimcp_list_phone_numbers and vapimcp_get_phone_number to find the phone number to call from.
• Use vapimcp_create_call to place an outbound call with a chosen assistant and phone number, then vapimcp_get_call to read its status, duration, and transcript.
• Use vapimcp_create_tool to add SMS, transfer-call, function, or API-request tools, and attach them to an assistant with vapimcp_update_assistant.

Node.js

const toolResponse = await actions.executeTool({
  connector: 'vapimcp',
  identifier: 'user_123',
  toolName: 'vapimcp_create_call',
  toolInput: {
    assistantId: 'YOUR_ASSISTANT_ID',
    phoneNumberId: 'YOUR_PHONE_NUMBER_ID',
    customer: { number: '+15551234567' },
  },
});
console.log('Call started:', toolResponse.data);

Python

tool_response = actions.execute_tool(
    connection_name='vapimcp',
    identifier='user_123',
    tool_name='vapimcp_create_call',
    tool_input={
        "assistantId": "YOUR_ASSISTANT_ID",
        "phoneNumberId": "YOUR_PHONE_NUMBER_ID",
        "customer": {"number": "+15551234567"},
    },
)
print("Call started:", tool_response)

Tool list

Use the exact tool names from the Tool list below when you call execute_tool. If you’re not sure which name to use, list the tools available for the current user first.

vapimcp_create_assistant#Creates a new Vapi voice AI assistant with the specified configuration. Configure the assistant's LLM provider, voice, transcription engine, first message, and any tools it should have access to.9 params▾

Creates a new Vapi voice AI assistant with the specified configuration. Configure the assistant's LLM provider, voice, transcription engine, first message, and any tools it should have access to.

NameTypeRequiredDescription

namestringrequiredName of the assistant

rationalestringrequiredAlways provide a brief explanation of why you are calling this tool

firstMessagestringoptionalFirst message the assistant says when a call starts

firstMessageModestringoptionalWhether the assistant speaks first or waits for the user

instructionsstringoptionalSystem instructions for the assistant. Defaults to 'You are a helpful assistant.'

llmstringoptionalLLM configuration. Defaults to OpenAI gpt-4o.

toolIdsstringoptionalIDs of Vapi tools to attach to this assistant

transcriberstringoptionalTranscription configuration. Defaults to Deepgram nova-3.

voicestringoptionalVoice configuration. Defaults to ElevenLabs 'sarah'.

vapimcp_create_call#Initiates or schedules an outbound Vapi call. Specify the assistant and phone number to use, the customer's phone number, and optionally a scheduled time. Use assistantOverrides.variableValues to inject dynamic data into the assistant's prompts.6 params▾

Initiates or schedules an outbound Vapi call. Specify the assistant and phone number to use, the customer's phone number, and optionally a scheduled time. Use assistantOverrides.variableValues to inject dynamic data into the assistant's prompts.

NameTypeRequiredDescription

rationalestringrequiredAlways provide a brief explanation of why you are calling this tool

assistantIdstringoptionalID of the Vapi assistant to use for the call

assistantOverridesstringoptionalRuntime overrides for the assistant configuration

customerstringoptionalCustomer contact information for the outbound call

phoneNumberIdstringoptionalID of the Vapi phone number to call from

scheduledAtstringoptionalISO 8601 datetime to schedule the call (e.g. 2025-03-25T22:39:27.771Z). Omit to call immediately.

vapimcp_create_tool#Creates a new Vapi tool that can be attached to assistants. Supports four tool types: 'sms' for sending text messages, 'transferCall' for transferring calls to destinations, 'function' for custom server-side functions, and 'apiRequest' for HTTP API integrations.8 params▾

Creates a new Vapi tool that can be attached to assistants. Supports four tool types: 'sms' for sending text messages, 'transferCall' for transferring calls to destinations, 'function' for custom server-side functions, and 'apiRequest' for HTTP API integrations.

NameTypeRequiredDescription

rationalestringrequiredAlways provide a brief explanation of why you are calling this tool

typestringrequiredType of tool to create

apiRequeststringoptionalAPI request tool configuration — provide when type is 'apiRequest'

descriptionstringoptionalDescription of what the tool does

functionstringoptionalFunction tool configuration — provide when type is 'function'

namestringoptionalName of the tool

smsstringoptionalSMS configuration — provide when type is 'sms'

transferCallstringoptionalTransfer call configuration — provide when type is 'transferCall'

vapimcp_get_assistant#Retrieves the full configuration of a specific Vapi assistant by ID, including its LLM, voice, transcription settings, tools, and first message.2 params▾

Retrieves the full configuration of a specific Vapi assistant by ID, including its LLM, voice, transcription settings, tools, and first message.

NameTypeRequiredDescription

assistantIdstringrequiredID of the assistant to retrieve

rationalestringrequiredAlways provide a brief explanation of why you are calling this tool

vapimcp_get_call#Retrieves detailed information about a specific Vapi call by ID, including its status, duration, transcript, recording URL, and associated assistant.2 params▾

Retrieves detailed information about a specific Vapi call by ID, including its status, duration, transcript, recording URL, and associated assistant.

NameTypeRequiredDescription

callIdstringrequiredID of the call to retrieve

rationalestringrequiredAlways provide a brief explanation of why you are calling this tool

vapimcp_get_phone_number#Retrieves details of a specific Vapi phone number by ID, including its number, provider, and any assistant or squad configuration attached to it.2 params▾

Retrieves details of a specific Vapi phone number by ID, including its number, provider, and any assistant or squad configuration attached to it.

NameTypeRequiredDescription

phoneNumberIdstringrequiredID of the phone number to retrieve

rationalestringrequiredAlways provide a brief explanation of why you are calling this tool

vapimcp_get_tool#Retrieves the full configuration of a specific Vapi tool by ID, including its type (SMS, transfer call, function, or API request) and associated settings.2 params▾

Retrieves the full configuration of a specific Vapi tool by ID, including its type (SMS, transfer call, function, or API request) and associated settings.

NameTypeRequiredDescription

rationalestringrequiredAlways provide a brief explanation of why you are calling this tool

toolIdstringrequiredID of the Vapi tool to retrieve

vapimcp_list_assistants#Lists all Vapi assistants configured in the account. Returns a list of assistant objects including their IDs, names, configurations, and settings.1 param▾

Lists all Vapi assistants configured in the account. Returns a list of assistant objects including their IDs, names, configurations, and settings.

NameTypeRequiredDescription

rationalestringrequiredAlways provide a brief explanation of why you are calling this tool

vapimcp_list_calls#Lists all Vapi calls in the account. Returns call records including their IDs, status, duration, associated assistant, and transcript metadata.1 param▾

Lists all Vapi calls in the account. Returns call records including their IDs, status, duration, associated assistant, and transcript metadata.

NameTypeRequiredDescription

rationalestringrequiredAlways provide a brief explanation of why you are calling this tool

vapimcp_list_phone_numbers#Lists all phone numbers provisioned in the Vapi account. Returns phone number objects including their IDs, numbers, provider, and associated assistant configurations.1 param▾

Lists all phone numbers provisioned in the Vapi account. Returns phone number objects including their IDs, numbers, provider, and associated assistant configurations.

NameTypeRequiredDescription

rationalestringrequiredAlways provide a brief explanation of why you are calling this tool

vapimcp_list_tools#Lists all Vapi tools configured in the account. Vapi tools extend assistant capabilities — types include SMS, transfer call, custom functions, and API request tools.1 param▾

Lists all Vapi tools configured in the account. Vapi tools extend assistant capabilities — types include SMS, transfer call, custom functions, and API request tools.

NameTypeRequiredDescription

rationalestringrequiredAlways provide a brief explanation of why you are calling this tool

vapimcp_update_assistant#Updates an existing Vapi assistant's configuration. Only fields you provide will be changed; omitted fields retain their current values.10 params▾

Updates an existing Vapi assistant's configuration. Only fields you provide will be changed; omitted fields retain their current values.

NameTypeRequiredDescription

assistantIdstringrequiredID of the assistant to update

rationalestringrequiredAlways provide a brief explanation of why you are calling this tool

firstMessagestringoptionalNew first message the assistant says when a call starts

firstMessageModestringoptionalNew first message mode

instructionsstringoptionalNew system instructions for the assistant

llmstringoptionalNew LLM configuration

namestringoptionalNew name for the assistant

toolIdsstringoptionalNew list of Vapi tool IDs for the assistant

transcriberstringoptionalNew transcription configuration

voicestringoptionalNew voice configuration

vapimcp_update_tool#Updates an existing Vapi tool's configuration. Only fields you provide will be changed. Supports all tool types: sms, transferCall, function, and apiRequest.8 params▾

Updates an existing Vapi tool's configuration. Only fields you provide will be changed. Supports all tool types: sms, transferCall, function, and apiRequest.

NameTypeRequiredDescription

rationalestringrequiredAlways provide a brief explanation of why you are calling this tool

toolIdstringrequiredID of the Vapi tool to update

apiRequeststringoptionalUpdated API request tool configuration

descriptionstringoptionalNew description for the tool

functionstringoptionalUpdated function tool configuration

namestringoptionalNew name for the tool

smsstringoptionalUpdated SMS configuration

transferCallstringoptionalUpdated transfer call configuration