The meta-model does not require that schema artifacts should require all the necessary fields in the @contexts of instances

[martinjoconnor]

Schema artifacts have have a JSON Schema specification for the contents of the @context in their corresponding instances.

However, the meta model does not require that the schema artifacts require that the specified fields are actually present in the intance contexts.

For example, the meta-schema specification for template a /properties/@context specification looks like the following:

{
    "description": "Meta-schema that describes the schema of a '@context' field in a 'properties' field in a template",
    "type": "object",
    "properties": {
        "type": { "type": "string", "enum": [ "object" ] },
        "properties": { "$ref": "file:templateContextPropertiesFieldContent.json" },
        "required": { "$ref": "file:stringArray.json" },
        "additionalProperties": {
          "oneOf": [
            { "$ref": "file:falseOnlyAdditionalProperties.json" },
            { "$ref": "file:uriOnlyAdditionalProperties.json" }
          ]
        }
    },
    "required": [ "type", "properties", "additionalProperties" ],
    "additionalProperties": false
}

The specification for required is:

 "required": { "$ref": "file:stringArray.json" },

It should list the required properties so that template forces them to be in insance @context specifications.

Similar problem for elements and fields.