# Prime-first boundary

Arena publishes Lumbridge environments; it does not implement another generic
harness, trainer, runtime marketplace, or environment hub.

- Every environment pins stable `verifiers==0.3.1`.
- Pure-trace environments select Verifiers' upstream `null` harness.
- Local model-free and the reference node runs name the `subprocess` runtime explicitly so
  tests never provision a paid Prime sandbox.
- Prime Hub is the public distribution target for approved environment wheels.
- Prime-RL consumes the same taskset packages for training; Forge owns the
  explicit training handoff and artifact rendering.

Lumbridge's unique work is the environment: task distributions, interactive
state, rewards, probes, held-out gates, and result interpretation. Tera bridges
are developed with Tera because they package proprietary simulator source; they
use the same upstream Verifiers contract without living in this public repo.
Generic rollout and training machinery stays upstream. A Hub publication must
exclude secrets, private task splits, customer data, and proprietary Tera source.

The preferred future compute path is Prime's spot market. GH200/GB300 names in
runbooks are desired hardware profiles, not a promise that inventory exists and
not authorization to rent it. An operator checks current Prime availability and
price before launching any paid run.