permission_challenge

permission_challenge

Two agents on two sessions. Generator proposes a patch; reviewer holds veto via permission.request. Same wire contract as a single agent asking a human.

Before ARCP

Two-agent code review is glued together with sidecars: generator writes a PR, CI runs a "reviewer" model, results posted as a comment. The reviewer can't say "deny: rewrite this hunk and try again" without manual loop wiring.

With ARCP

let lease = request_apply(&generator, ticket_id, &patch).await;
match lease {
    Err(ARCPError::PermissionDenied { detail }) => prior_denial = Some(detail),
    Ok(_)  => return Ok(()),  // applied
    Err(e) => return Err(e.into()),
}

Idempotency key per (ticket, diff) lets identical patches dedupe at the runtime — re-proposing the same diff returns the prior verdict.

ARCP primitives

• permission.request with structured reason and a tight requested_lease_seconds — §15.4.
• permission.grant / permission.deny with typed code — §15.4.
• idempotency_key for retry-safe re-asks — §6.4.

File tour

• main.rs — generator side proposes; reviewer loop on a second session responds.
• agents.rs — propose + review LLM stubs.

Variations

• Three reviewers, majority-grant.
• A permission.request with min_reviewers: 2 carried in extensions.
• Promote the deny into structured feedback the generator parses.