avro.io.AvroTypeException

[zhengxiuya]

Hello：
I download this quikstart,and it can run well ,but when i change it add an type [add] to this avpr ,and change the messages-send like :"send": { "request": [{"name": "message", "type": "Message"},{"name": "add", "type": "Add"}], then i call send method get then error:avro.io.AvroTypeException. I don't know how to call then method send. then avpr is like:
{"namespace": "example.proto",
"protocol": "Mail",

"types": [
{"name": "Message", "type": "record",
"fields": [
{"name": "to", "type": "string"},
{"name": "from", "type": "string"},
{"name": "body", "type": "string"}
]
}, {"name": "Add", "type": "record",
"fields": [
{"name": "name", "type": "string"},
{"name": "id", "type": "string"},
{"name": "code", "type": "string"}
]
}
],

"messages": {
"send": {
"request": [{"name": "message", "type": "Message"},{"name": "add", "type": "Add"}],
"response": "string"
}
}
}

hope for help!
thinks