client.json

{
    "operations": {
        "GetMessages": {
            "httpMethod": "GET",
            "uri": "/messages",
            "summary": "Gets a list of messages",
            "responseClass": "GetMessagesOutput"
        },
        "GetMessage": {
            "httpMethod": "GET",
            "uri": "/messages/{id}",
            "summary": "Retrieves a single message",
            "responseClass": "GetMessageOutput",
            "parameters": {
                "id": {
                    "location": "uri",
                    "description": "Message to retrieve by ID",
                    "required": true
                }
            }
        }
    },
    "models": {
        "Message": {
            "type": "object",
            "properties": {
                "id": {
                    "location": "json",
                    "type": "integer"
                },
                "subject": {
                    "location": "json",
                    "type": "string"
                },
                "text": {
                    "location": "json",
                    "type": "string"
                }
            }
        },
        "GetMessagesOutput": {
            "type": "object",
            "additionalProperties": {
                "location": "json",
                "type": "object",
                "properties": {
                    "id": {
                        "location": "json",
                        "type": "integer"
                    },
                    "subject": {
                        "location": "json",
                        "type": "string"
                    },
                    "text": {
                        "location": "json",
                        "type": "string"
                    }
                }
            }
        },
        "GetMessageOutput": {
            "$ref": "Message"
        }
    }
}

client2.json

{
    "operations": {
        "GetMessages": {
            "httpMethod": "GET",
            "uri": "/messages",
            "summary": "Gets a list of messages",
            "responseClass": "GetMessagesOutput"
        },
        "GetMessage": {
            "httpMethod": "GET",
            "uri": "/messages/{id}",
            "summary": "Retrieves a single message",
            "responseClass": "GetMessageOutput",
            "parameters": {
                "id": {
                    "location": "uri",
                    "description": "Message to retrieve by ID",
                    "required": true
                }
            }
        }
    },
    "models": {
        "Message": {
            "type": "object",
            "properties": {
                "id": {
                    "location": "json",
                    "type": "integer"
                },
                "subject": {
                    "location": "json",
                    "type": "string"
                },
                "text": {
                    "location": "json",
                    "type": "string"
                }
            }
        },
        "GetMessagesOutput": {
            "type": "object",
            "additionalProperties": {
                "location": "json",
                "$ref": "Message"
            }
        },
        "GetMessageOutput": {
            "$ref": "Message"
        }
    }
}