ignoring how the GraphQl engine is implemented for a moment, the following model makes a lot of sense from a user's perspective:

ScopedValue.where(GRAPHQL_CONTEXT, ...env. getGraphQlContext?...).run(() -> dataFetcher(env))

I would go as far as allowing the user to register dependent bindings with graphql-java:

graphQlJava.registerScopedValues((env, carrier) -> carrier.whrere(MY_SCOPED_VALUE, env.getLocalContext.get("SOME_KEY")))

And the engine would invoke the registrations before running the data fetcher.

The end goal? Access your own scoped values in your domain code without depending on Spring, graphql-java or micrometer:

class DomanClasss {
  boolean canView() {
    USER.get().permissions().contains(XXX)
    TENANT.get().entitlements().contains(YYY)
    CLOCK.get().instant().isAfter(...)
  }
}

You set your scoped values through datafetchers:

        return DataFetcherResult.newResult()
                .data(data)
                .localContext(GraphQLContext.newContext()
                        .of("tenant", tenant)
                        .build())
                .build();

Following the above datafecher, children fields will have access to the scoped values. And graphql-java wouldn't propagate it up the query(normal localContext behavior).

The benefit over TheradLocals is the fact the bindings go one way(down the stack), you don't have to worry about some callee polluting your SocepdValue.

Coming back to how the GraphQl engine is implemented. the engine can keep track of ScopedValue.Carrier as it's resolving fields, binding all accumulated SocpedValues before executing the datafetcher. This is roughly what is already happening with the localContext.

SocpedValues work well with structured concurrency but they don't depend on each other. Without structured concurrency they will a better TheradLocal(one way data flow, rebinding on the way down, unbinding on the way).

As for Java 25 baseline, it can be done without APIs depending on 25(I think). And reflection can be used for the runtime side(I assume it's possible)

As I'm writing this I struggling with context propagation in spring-graphql 😅🤕

Make getGraphQlContext and getLocalContext available as ScopedValues #4120

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