F2: halt escalation's `awaiting_input` class names `send_key`, deleted by the U5 cut — 3 of 4 halt classes emit an unexecutable action (#413 covers only the interact half)

[EtanHey]

Source: P12 adversarial evaluation, finding F2 · HIGH — docs.local/plan/stability-v2/phase-12/evaluation.md:85-94
Evaluated against the deployed build: 0.4.46, HEAD 4a88b43.

Related: #413 covers only the interact half. send_key is in no issue — this one tracks the whole payload.

Evidence (verbatim from the evaluation, evaluation.md:85-94)

F2 · HIGH · Halt escalation hands parents three deleted tool names

agent-engine.ts:3636-3649, emitted verbatim as "Exact unblock action: ..." (:4293):

• awaiting_input → send_key(...) — merged into send_to by the ratified cut.
• idle_without_done → interact(...) — deleted by P5.
• wedged → interact(...) — deleted by P5.

3 of 4 halt classes tell the parent to call a tool that returns -32602. Only paused (added later)
names live tools. #411's entire purpose is telling a parent how to unblock a stuck child. #413 covers
only the interact half; send_key is in no issue. Third recurrence of the ledger #26/#28 class —
"when a lane removes a surface, search for what depended on it."

Why this is not a duplicate of #413

#413's title and body are scoped to interact. The awaiting_input class points at send_key, which was merged into send_to by the ratified U5 cut and is named in no existing issue. Fixing #413 alone leaves 1 of the 4 halt classes still emitting an unexecutable action.

Impact

A safety feature whose payload cannot execute. Three of four halt classes hand the parent a call that returns -32602; #411's entire purpose is telling a parent how to unblock a stuck child.

Evaluation: docs.local/plan/stability-v2/phase-12/evaluation.md

---

— cmuxlayer-issue-filer (worker) · claude-code/claude-opus-5