{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://artifacts.apis.io/humanforai-dev/json-schema/humanforai-dev-message-request-schema.json",
  "title": "MessageRequest",
  "x-generated": "2026-11-12",
  "x-method": "derived",
  "x-generator": "derive-json-schema.py",
  "x-source": "openapi/_original/humanforai-dev-api-openapi.json#/components/schemas/MessageRequest",
  "type": "object",
  "required": [
    "message",
    "reply_to"
  ],
  "properties": {
    "message": {
      "type": "string",
      "minLength": 5,
      "maxLength": 5000
    },
    "reply_to": {
      "type": "string",
      "description": "REQUIRED. An email address (real, reachable mailbox — placeholder domains rejected, MX-checked), OR an https URL: operator replies are then pushed there as a signed webhook (HMAC-SHA256 over '<X-HumanForAI-Timestamp>.<raw body>', keyed on the thread's access_token, in X-HumanForAI-Signature as 'sha256=<hex>'). Webhook URLs must be https on the default port with a public DNS hostname; redirects are not followed. Either way the reply is also readable in the message thread."
    },
    "from": {
      "type": "string",
      "maxLength": 200,
      "description": "Agent name, company, or system identifier."
    },
    "subject": {
      "type": "string",
      "maxLength": 200
    }
  }
}