delegate_task gains a control plane: action='list' / 'steer' / 'stop'
let the parent agent see, redirect, and early-stop its own running
subagents mid-flight — the model-facing counterpart of the TUI's
delegation.pause / subagent.interrupt / subagent.steer RPCs.
- action='list': live children of this conversation's spawn tree
(ids, goal, status, running_seconds, accepting_steer, live
transcript path). Ownership is enforced via a _delegate_parent_ref
weakref chain stamped at child build time, so a conversation can
only control its own descendants, never a sibling tree.
- action='steer': queues text into a running child via the existing
steer_subagent() registry path (delivered at the child's next tool
boundary; missed steers surface as missed_steer in the completion).
- action='stop': interrupt_subagent() — child stops at its next
iteration boundary, partial result still re-enters as a completion.
- Spawn dispatch response now includes subagent_ids + control hint.
- Control actions run synchronously (never backgrounded) and bypass
the spawn pause gate and depth limit; they also never consume the
per-turn subagent spawn cap, and remain usable once the cap is hit
(that is when stop matters most).
- Small-model robustness (found live with gpt-5.4-mini on Nous
Portal): tasks=[] alongside goal no longer trips the "Batch mode
requires at least 2 tasks" gate — treated as single-goal.
- CLI display: control calls render as "steer sa-…" / "list" instead
of an empty goal.
Live-tested E2E on Nous Portal (fable-5 + gpt-5.4-mini): full
spawn→list→steer→stop cycle, plus a steer-efficacy run where the
child acked the steer mid-essay and switched topics before finishing.
Teknium