Validate that all `Required` function calling parameters exist in the Schema

[fredsa]

Using github.com/google/generative-ai-go v0.11.0, this code does not complain about the "this_param_does_not_exist" entry in the Required field.

	currencyExchange := &genai.Tool{
		FunctionDeclarations: []*genai.FunctionDeclaration{{
			Name:        "get_exchange_rate",
			Description: "Lookup currency exchange rates by date",
			Parameters: &genai.Schema{
				Type: genai.TypeObject,
				Properties: map[string]*genai.Schema{
					"currency_date": {
						Type: genai.TypeString,
						Description: "A date that must always be in YYYY-MM-DD format" +
							" or the value 'latest' if a time period is not specified",
					},
					"currency_from": {
						Type:        genai.TypeString,
						Description: "Currency to convert from",
					},
					"currency_to": {
						Type:        genai.TypeString,
						Description: "Currency to convert to",
					},
				},
                                 // Note, "this_param_does_not_exist".
				Required: []string{"currency_date", "currency_from", "this_param_does_not_exist"},
			},
		}},
	}

To help developers, it would be immensely valuable to validate the Required field values.

[jba]

Isn't that something the service should do, not the client? The client generally tries to do minimal validation or manipulation of requests to the service.

[fredsa]

That would be fine as well. Though, I suspect it will be easier for the client library / SDK to provide a much more useful message to the developer, though admittedly at the cost of duplicate complexity across all language client libraries / SDKs.

In short, happy to have the validation happen in either place.