{
  "id": "core-06-protocol-mismatch",
  "title": "Protocol mismatch is rejected",
  "category": "core",
  "version": "aicc/0.1",
  "description": "A message with a wrong protocol version must be rejected with protocol_mismatch.",
  "steps": [
    {
      "send": {
        "protocol": "aicc/0.2",
        "type": "tool_call",
        "tool": "echo",
        "input": {}
      }
    },
    {
      "expect": {
        "type": "error",
        "error": {
          "code": "protocol_mismatch",
          "retryable": false
        }
      }
    }
  ]
}