abcd-runs-a-delegated-agent-through-a-command-line-model-run

Summary

The design record for itd-2609201916056194: one runner interface, a route per role, a configured fallback and the fallback as recorded intel.

Scope

1. The interface (internal/core/runner): Run(role, brief, contract) (answer, transcript, err); the host implementation is the existing sub-agent dispatch, so the loop calls one thing (criteria 1, 2).
2. The adapters: claude (print mode, bare, structured output, allowed tools from the role's contract) and opencode (run mode, or the server's session and prompt endpoints where a server is already up); each parses the harness's structured events into the one answer shape and writes the transcript to abcd's store (criteria 1, 6, 7).
3. The route: roles.<role>.runner through the layered resolver; unset is host (criterion 2).
4. The fallback: one place decides it (runner error, absent binary, non-zero exit, unparsable answer); it calls the host implementation, or runner.fallback_host when no host session is present, and appends a receipt to the run's state; the summary counts them (criteria 3, 4).
5. The allowlist resolved before launch (adr-2609221009491186) (criterion 5).
6. Review: security reviewer on the lane (criterion 8).

Out of scope

• The tier's choice; installing a harness; a served console.

Approach

The runner interface is the same shape the validator stage already defines for reviewers, so a role's route is one lookup; the fallback is one branch with one receipt writer, which is what makes the count trustworthy.

Footprint

• packages: internal/core/runner, internal/core/implement, internal/surface/cli
• tests: each adapter against a fake harness binary; the fallback receipt on each failure kind; the count in the summary; the allowlist refusal; the bare flag asserted in the launch

How the criteria are satisfied

Progress

The spec stays open: the live proof is owed (iss-2609301519558538) and no ruling yet lets the intent close on fake harnesses.

• Landed: scopes 1 to 5 in the core (internal/core/runner): the runner interface and the one dispatcher, the claude adapter (print mode, --bare, stream-json, --permission-mode dontAsk, the role's tools allowed) and the opencode adapter (run mode, JSON events, --pure), the route through the layered resolver, the fallback with one receipt writer and Tally, and the allowlist admitted at the read and again before a launch; a model a provider lists is admitted by its allowlist alone and refused only by a configured oracle.denylist entry (adr-2609300107513982).
• Landed: the loop wiring (spc-2609202134338445 piece 3): implement step drives through loop.Drive, which starts a routed role through the dispatcher with the brief and receipt path the host would get, validates its answer with the stage's own receipt verifier, stores its transcript in abcd's history store, and stamps the verified receipt or recorded return with the route that ran it (criteria 1 and 7, structurally); an unset role leaves the step and the state byte-identical (criterion 2); a fallback is recorded in the state's fallbacks and the record (criterion 3) and counted per runner and per role by implement status and implement record (criterion 4); build and step refuse a runner configuration fault, a model off its allowlist included, before anything is created or launched (criterion 5). The bare flag is asserted in the launch (criterion 6).
• Not built: the no-host path at the surface. runner.fallback_host works in the core, but a surface that runs without a host session is the process driver's reversal of the host-delegated boundary, which waits on itd-2609201916151817's decision-6 ADR.
• Owed: the live proof of criterion 7 and the phase-1 unverified points (iss-2609301519558538), and criterion 8, the security review, which the lane's report lists point by point for the reviewer.