public FixedQuery posBoundingBox(double n, double s, double e, double w) {
        this.param("pos.bb", Text.format("n=%f,s=%f,e=%f,w=%f", n, s, e, w));
        return this;
    }
FixedQuery contains a 'Query'.
This object holds vespa or user defined parameters
https://docs.vespa.ai/en/reference/query-api-reference.html
client/src/main/java/ai/vespa/client/dsl/FixedQuery.java