What problem does it solve? When an evaluator runs in a separate lane from the system under build, determining how it reaches that system over a private network is error-prone — especially across rootful versus rootless Docker engines and different substrates. This Skill deterministically resolves the correct base host so the evaluator can reach the system without application-layer authentication. ## Core Features & Use Cases - Deterministic topology resolution: Switches on the evaluator_topology field of the provision context — co-resident returns localhost, dind-in-cage and cross-machine trigger re-basing — never inferring from ambiguous signals. - Rootless-aware Docker handling: Detects rootless Docker engines via docker info and selects a shared user-defined network instead of the host-gateway address, which does not route under rootless. - Substrate branches: Covers local docker-in-docker today and documents the Fly 6PN (private IPv6) branch for cross-machine follow-ons, returning optional teardown instructions for transient networking artifacts. - Use Case: During an L4 unattended delivery run, the env occupant calls this transport slot to learn that the evaluator container must reach the system under build via a shared Docker network alias, then threads that host through the validated --base-host seam. ## Quick Start Compose this Skill into the transport slot of an env configuration and let it resolve the evaluator base host from the provision context automatically.
