Phantom identifier of a capability in the Effect context.
Branded by the capability's NSID (a string literal) and arity — never by the service type —
so the requirement channel names only local string literals, keeping module bodies'
declaration emit portable without per-file annotations. This mirrors Effect's own tags, whose
requirement identity is a nominal token (the Self class of Context.Tag/Effect.Service),
never the structural service shape. Arity keeps singleton and multi capabilities from crossing APIs.
Phantom identifier of a capability in the Effect context. Branded by the capability's NSID (a string literal) and arity — never by the service type — so the requirement channel names only local string literals, keeping module bodies' declaration emit portable without per-file annotations. This mirrors Effect's own tags, whose requirement identity is a nominal token (the
Selfclass ofContext.Tag/Effect.Service), never the structural service shape. Arity keeps singleton and multi capabilities from crossing APIs.