JsonPointer

A JSON Pointer (RFC 6901) into a surface's data model.

A2UI uses pointers for two things that RFC 6901 does not distinguish, so this type carries the distinction as isAbsolute:

• An absolute pointer (/user/name, or the empty string) resolves from the root of the data model no matter where the component using it sits in the UI tree.

• A relative pointer (name) resolves from the item currently being iterated by the enclosing list template — see EvaluationScope. RFC 6901 has no such form: every pointer it defines either is empty or begins with /.

Deviation from RFC 6901, required by the specification. Under the RFC, / is a pointer to the member whose name is the empty string, and only "" addresses the whole document. A2UI instead says of updateDataModel.path: "If omitted, or set to /, refers to the entire data model." This type follows A2UI, so "" and / both parse to ROOT and there is no way to write a pointer to a top-level "" key. The alternative — following the RFC and reading / as a key — would silently write agent payloads into the wrong place.