Current progress on T2719, notably, PR #1351: "prototype of an op mode command runner based on type hints and introspection", allow one to automate the creation of corresponding GraphQL schema definition files. The current generating script is linked below. Resolvers (handlers) for these definitions are already dynamically generated, although still requiring that the named resolvers be added by hand to a list; that step will be automated as well, resulting in one only having to run the script to allow server response to any GraphQL op-mode request.
https://github.com/jestabro/vyos-1x/blob/gql-op-mode-merge/src/services/api/graphql/utils/schema_from_op_mode.py