Vapi · Schema

ClientMessage

Artificial IntelligenceVoiceAgentsReal-TimeCPaaS

Properties

Name Type Description
message object These are all the messages that can be sent to the client-side SDKs during the call. Configure the messages you'd like to receive in `assistant.clientMessages`.
View JSON Schema on GitHub

JSON Schema

vapi-clientmessage-schema.json Raw ↑
{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "#/components/schemas/ClientMessage",
  "title": "ClientMessage",
  "type": "object",
  "properties": {
    "message": {
      "description": "These are all the messages that can be sent to the client-side SDKs during the call. Configure the messages you'd like to receive in `assistant.clientMessages`.",
      "oneOf": [
        {
          "$ref": "#/components/schemas/ClientMessageWorkflowNodeStarted",
          "title": "WorkflowNodeStarted"
        },
        {
          "$ref": "#/components/schemas/ClientMessageAssistantStarted",
          "title": "AssistantStarted"
        },
        {
          "$ref": "#/components/schemas/ClientMessageConversationUpdate",
          "title": "ConversationUpdate"
        },
        {
          "$ref": "#/components/schemas/ClientMessageHang",
          "title": "Hang"
        },
        {
          "$ref": "#/components/schemas/ClientMessageMetadata",
          "title": "Metadata"
        },
        {
          "$ref": "#/components/schemas/ClientMessageModelOutput",
          "title": "ModelOutput"
        },
        {
          "$ref": "#/components/schemas/ClientMessageSpeechUpdate",
          "title": "SpeechUpdate"
        },
        {
          "$ref": "#/components/schemas/ClientMessageTranscript",
          "title": "Transcript"
        },
        {
          "$ref": "#/components/schemas/ClientMessageToolCalls",
          "title": "ToolCalls"
        },
        {
          "$ref": "#/components/schemas/ClientMessageToolCallsResult",
          "title": "ToolCallsResult"
        },
        {
          "$ref": "#/components/schemas/ClientMessageTransferUpdate",
          "title": "TransferUpdate"
        },
        {
          "$ref": "#/components/schemas/ClientMessageUserInterrupted",
          "title": "UserInterrupted"
        },
        {
          "$ref": "#/components/schemas/ClientMessageLanguageChangeDetected",
          "title": "LanguageChangeDetected"
        },
        {
          "$ref": "#/components/schemas/ClientMessageVoiceInput",
          "title": "VoiceInput"
        },
        {
          "$ref": "#/components/schemas/ClientMessageAssistantSpeech",
          "title": "AssistantSpeech"
        },
        {
          "$ref": "#/components/schemas/ClientMessageChatCreated",
          "title": "ChatCreated"
        },
        {
          "$ref": "#/components/schemas/ClientMessageChatDeleted",
          "title": "ChatDeleted"
        },
        {
          "$ref": "#/components/schemas/ClientMessageSessionCreated",
          "title": "SessionCreated"
        },
        {
          "$ref": "#/components/schemas/ClientMessageSessionUpdated",
          "title": "SessionUpdated"
        },
        {
          "$ref": "#/components/schemas/ClientMessageSessionDeleted",
          "title": "SessionDeleted"
        },
        {
          "$ref": "#/components/schemas/ClientMessageCallDeleted",
          "title": "CallDeleted"
        },
        {
          "$ref": "#/components/schemas/ClientMessageCallDeleteFailed",
          "title": "CallDeleteFailed"
        }
      ]
    }
  },
  "required": [
    "message"
  ]
}

Work with this as data

Every JSON Schema here is available over the APIs.io API and to AI agents over MCP.

MCP server

One button, every client — Claude, Cursor, VS Code and the rest.

https://apis.io/mcp

Tools for schemas

4 MCP tools reach this
  • find_json_schemasBrowse and filter every JSON Schema in the catalog.
  • apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
  • resolveTurn a domain, URL or GitHub org into the provider it belongs to.
  • find_cohortsEvery scored population of providers in the catalog.
All 92 tools

Call it yourself

curl for this page
This JSON Schema
curl "https://apis.io/api/v1/json-schemas/vapi-clientmessage"
All schemas
curl "https://apis.io/api/v1/json-schemas?limit=25"

Discovery needs no key. Ratings and market analysis are Pro.

Get an API key

Free tier, no email required.

A second provider on the same verified email joins the account you already have.