json_schema: {
    "$schema": "http://json-schema.org/draft-04/schema#",
    "title": "VW Example",
    "type": "array",
    "description": "A stream of examples sent to the VW web service, which will submit them to VW",
    "items": {
      "type": "object",
      "description": "An individual example in the stream",
      "properties": {
        "label": {
          "type": "string",
          "description": "The label for the example. Can be null/empty, but can contain anything",
          "minLength": 0
        },
        "tag": {
          "type": "string",
          "description": "The tag for the example. Can be null/empty, but can contain anything",
          "minLength": 0
        },
        "namespaces": {
          "type": "array",
          "description": "The list of namespaces in the example",
          "items": {
            "type": "object",
            "description": "An individual namespace inside an example",
            "properties": {
              "name": {
                "type": "string",
                "description": "The name of the namespace. Can be null/empty, but must not contain whitespace, | or :",
                "minLength": 0
              },
              "scale": {
                "type": "number",
                "description": "The scaling factor for the namespace, optional - defaults to 1 if not present - name must be present for this to be accepted"
              },
              "features": {
                "type": "array",
                "description": "The list of features in this namespace",
                "items": {
                  "type": "object",
                  "description": "An individual feature inside a namespace",
                  "properties": {
                    "name": {
                      "type": "string",
                      "description": "The name of the feature. Must be present",
                      "minLength": 1
                    },
                    "value": {
                      "type": "number",
                      "description": "The value of the feature. Defaults to 1 if not present"
                    }
                  },
                  "additionalProperties": false,
                  "required": [
                    "name"
                  ]
                },
                "minItems": 0,
                "_uniqueItems": false,
                "additionalItems": false
              }
            },
            "minProperties": 0,
            "additionalProperties": false
          }
        }
      },
      "minProperties": 0,
      "additionalProperties": false
    },
    "minItems": 0,
    "_uniqueItems": false,
    "additionalItems": false
  }
  