Function eval_image 

pub fn eval_image(
    registry: &str,
    benchmark: &str,
    agent: &str,
    tag: &str,
) -> String

{registry}/evals/<benchmark>--<agent>:<tag> — the combined eval image (shared-env benchmarks: one image, task chosen at runtime). The -- separator is load-bearing: the OpenShift flattener collapses it to a single - for imagestream names (see flatten_imagestream).