{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "#/components/schemas/LettaMessageUnion",
  "title": "LettaMessageUnion",
  "oneOf": [
    {
      "$ref": "#/components/schemas/SystemMessage"
    },
    {
      "$ref": "#/components/schemas/UserMessage"
    },
    {
      "$ref": "#/components/schemas/ReasoningMessage"
    },
    {
      "$ref": "#/components/schemas/HiddenReasoningMessage"
    },
    {
      "$ref": "#/components/schemas/ToolCallMessage"
    },
    {
      "$ref": "#/components/schemas/ToolReturnMessage"
    },
    {
      "$ref": "#/components/schemas/AssistantMessage"
    },
    {
      "$ref": "#/components/schemas/ApprovalRequestMessage"
    },
    {
      "$ref": "#/components/schemas/ApprovalResponseMessage"
    },
    {
      "$ref": "#/components/schemas/SummaryMessage"
    },
    {
      "$ref": "#/components/schemas/EventMessage"
    }
  ],
  "discriminator": {
    "propertyName": "message_type",
    "mapping": {
      "system_message": "#/components/schemas/SystemMessage",
      "user_message": "#/components/schemas/UserMessage",
      "reasoning_message": "#/components/schemas/ReasoningMessage",
      "hidden_reasoning_message": "#/components/schemas/HiddenReasoningMessage",
      "tool_call_message": "#/components/schemas/ToolCallMessage",
      "tool_return_message": "#/components/schemas/ToolReturnMessage",
      "assistant_message": "#/components/schemas/AssistantMessage",
      "approval_request_message": "#/components/schemas/ApprovalRequestMessage",
      "approval_response_message": "#/components/schemas/ApprovalResponseMessage",
      "summary_message": "#/components/schemas/SummaryMessage",
      "event_message": "#/components/schemas/EventMessage"
    }
  }
}