{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://git.eeqj.de/sneak/chat/schema/message.schema.json",
  "title": "Chat Message Envelope",
  "description": "Base message envelope. Bodies MUST be objects or arrays (never raw strings) for deterministic canonicalization (RFC 8785 JCS) and signing.",
  "type": "object",
  "required": [
    "command"
  ],
  "properties": {
    "id": {
      "type": "string",
      "format": "uuid",
      "description": "Server-assigned UUID"
    },
    "ts": {
      "type": "string",
      "format": "date-time",
      "description": "Server-assigned timestamp (ISO 8601)"
    },
    "command": {
      "type": "string",
      "description": "IRC command name or numeric reply code"
    },
    "from": {
      "type": "string",
      "description": "Sender nick or server name"
    },
    "to": {
      "type": "string",
      "description": "Destination: channel (#foo) or nick"
    },
    "params": {
      "type": "array",
      "items": {
        "type": "string"
      },
      "description": "Additional IRC-style parameters"
    },
    "body": {
      "oneOf": [
        {
          "type": "array"
        },
        {
          "type": "object"
        }
      ],
      "description": "Message body (array or object, never raw string)"
    },
    "meta": {
      "type": "object",
      "description": "Extensible metadata",
      "properties": {
        "sig": {
          "type": "string",
          "description": "Cryptographic signature (base64)"
        },
        "alg": {
          "type": "string",
          "description": "Signature algorithm (e.g. ed25519)"
        }
      }
    }
  },
  "additionalProperties": false
}