D2’s re-evaluation command is aegis recheck, not aegis replay

Status: accepted (2026-08-10) · lands in AILAB-622 · edits Execution Report §6.4

AILAB-622 takes a recorded session plus a new policy set, re-evaluates every recorded decision, and emits a would-block diff. It executes nothing. That is not a replay, and calling it one promises effects that do not re-run. The command is aegis recheck --policy new.yaml session.<ext> — the extension is deliberately unresolved here, because .aar is ruled out below.

This was framed initially as a namespace collision with REPLAY’s aegis replay (AILAB-677, R2), to be solved by nesting D2’s verbs under the spec name. That was the wrong diagnosis. The two operations were never competing for one verb — one of them was wearing the other’s name. REPLAY’s operation genuinely is a replay; D2’s is a policy what-if against a record.

Why not namespace instead

Nesting (aegis aar verify / aegis aar replay) preserves the misnomer behind a longer path, and costs three things:

• It splits record verbs across two levels. aegis verify session.<ext> is the D4 exit criterion — the first thing a stranger types. Leaving verify top-level while nesting replay makes operation location unpredictable; moving verify down too lengthens the flagship command exactly where discoverability matters most.
• It reserves the best verb for work that may never ship. R2 is 12–24 months out and the direction decision says REPLAY phases do not become sprint scope without an explicit call. Paying UX cost in D2 to hold a name for that is speculative.
• Its main benefit is already delivered by the file extension. Every invocation reads … session.<ext>, so the format’s name is taught by the filename a user types a dozen times. No verb nesting required.

Nesting also would have left two operations on one verb dispatched by file type — implicit dispatch that is surprising when it works and confusing when it does not.

Consequences

• This is the same overclaim discipline as the rest of D2. Exit 0 on an unanchored file, “verified” for an internally-checked chain, an audit record claiming confinement the kernel did not apply — and a verb promising effects that do not re-run. The CLI verb is the most-read surface in the product.
• reeval is the fallback if recheck reads too casually for auditors. Avoid simulate — REPLAY §14 Mode E already claims it, and using it here recreates this collision one layer down. Avoid audit, already a pipeline station name.
• Cheap now, expensive later. 622 is unstarted and report §6.4’s aegis replay --policy new.yaml is a one-line edit. After a published README it is a breaking rename.
• The spec name is decoupled and stays with the PM (report §11.4). “Agent Action Record” is a sound prose name and, critically, vendor-neutral — a competitor can emit Agent Action Records without endorsing us; nobody would emit “Aegis Records.” That property is what §11.4 is really protecting.
• .aar must not be the file extension. It is the Android Archive format — a hard collision, because it is an extension we would be claiming. Editors and file will misidentify records as zip archives, GitHub’s language detection is already trained on it, and searches for the format spec return Android results indefinitely. .aarl signals both the acronym and the JSONL shape. The prose name and the extension are separate decisions.
• After-action report is a soft collision — same letters, and in audit circles it denotes a human-written retrospective. Survivable in prose; noted so the pitch does not lean on the acronym alone.