Route by predicate, first matching case wins, falling back to default. Each case names a predicate resolved at build time from the builder's predicate registry (behavior is not serialized — only the hook name). An unknown name fails the build loudly.

ByType

@Serializable

@SerialName(value = "byType")

data class ByType(val branches: List<TypeBranch>, val default: String) : RoutingSpec

Route by the instance's type id, falling back to default.

Direct

@Serializable

@SerialName(value = "direct")

data class Direct(val to: String) : RoutingSpec

Route directly to the node named to.

ShortestQueue

@Serializable

@SerialName(value = "shortestQueue")

data class ShortestQueue(val among: List<String>) : RoutingSpec

Route to whichever of among currently has the least work in process.