what documentation did you base this notation on? Node happens to use : for its named fragments, but just because that's how Node does it doesn't mean our API will always be implemented in Node, so let's use a syntax that does not rely on the specific technology used in the implementation. Also note that if it's part of the URI proper, it's not a "call parameter" so much as just part of the URI. If it were a `...?email=...` query argument, it might be a call parameter.