c6d2eeea6b
agent/steering was the last transient mirror of a durable session event:
drainSteering appended the durable steering/message {turn, content, source}
and emitted the identical fact one line later. Zero production listeners
existed — every steering consumer (hook bridges, goldens, deriveMessages)
reads the durable event — and the one regression test subscriber asserted
a fact the log already records.
Remove the declaration (dsh-agent types + JSDoc list + README row), the
emit in drainSteering (its ctx parameter goes too), and the emit line in
the loop-pseudocode blocks (loop.ts module doc, architecture.md); the
cordis catalog is regenerated. The regression test now pins source
preservation on the durable steering/message event. Live-notification
needs keep their surviving homes: agent/queued at enqueue time,
session/event at drain time.
RFC: docs/rfc/implemented/simplification/2026-07-04-remove-agent-steering-mirror.md
(moved from proposed/, amended to shipped reality). The three implemented
RFCs that stated the retention — the boundary-mirror removal, the
stream-chunk removal, and event-domain-semantics — are amended to point
at that RFC as the record of the removal, per implemented/AGENTS.md.
The rejected retire-mid-turn-steering RFC keeps its frozen text (it
records the declined proposal); the steering capability itself —
steer(), the durable event, continuation forcing — is untouched.
4.2 KiB
RFC: Remove the agent/steering mirror emit
Status: implemented (accepted 2026-07-04)
Problem
agent/steering was the last remaining transient mirror of a durable session event. The loop's steering drain appends the durable steering/message { turn, content, source } and, on the very next line, emitted agent/steering(agent, turn, content, source) — the identical fact as a fire-and-forget event (packages/core/agent-loop/src/loop.ts, drainSteering). It had zero production listeners: the only subscriber anywhere was a loop regression test asserting the emit carried source — the same fact the durable event already records one line above.
Both mirror-removal RFCs retained it while explicitly deferring the decision this RFC makes. The boundary-mirror removal kept it as a live control signal rather than a boundary; the stream-chunk removal retained it on the reading that it had no durable twin. The second rationale did not survive the code: the durable twin is steering/message, appended immediately before the emit with the same payload. The mirrored-vs-live-only line the taxonomy actually draws puts it on the mirror side: agent/queued is genuinely live-only (it fires at enqueue time, before any durable event exists, and already carries a steering: boolean flag — cancelled queued work never enters the log), while agent/steering fired at the exact moment its durable twin landed, carrying nothing the log does not.
Steering carries real production traffic — the hook bridges' turn-continuation decisions inject their reasons through inbox.steer(), landing as durable steering/message events that the hook-matrix goldens pin — and every one of those consumers observes the durable event. Nothing observed the mirror.
Decision
agent/steering is removed from the agent event taxonomy: the declaration in packages/core/agent/src/types.ts (and its mention in the live-events JSDoc list there), the emit in drainSteering (whose then-unused ctx parameter went with it), the row in packages/core/agent/README.md, and the emit line in the loop-pseudocode blocks (the packages/core/agent-loop/src/loop.ts module doc and architecture.md); the cordis catalog is regenerated without it. The one regression test pins source preservation on the durable steering/message event — the fact it pins lives on the log.
Three implemented RFCs stated the retention, and each is amended per implemented/AGENTS.md to point here as the record of the removal: the boundary RFC's retained-list entry, the stream-chunk RFC's scope clause, and the event-domain-semantics RFC's transient-emit enumeration.
Why not keep it?
"It is a control signal, not a boundary" — but the taxonomy's operative distinction is mirrored-vs-live-only, not control-vs-boundary, and this event mirrored. A consumer that wants enqueue-time notification has agent/queued (with its steering flag); a consumer that wants drain-time notification is by definition asking for the moment steering/message is appended, which session/event delivers with the same payload plus durability. The rejected retire-mid-turn-steering RFC defended the steering capability — steer(), the durable event, continuation forcing — all of which this removal keeps untouched.
Acceptance criteria
- The
agent/steeringspelling survives only in RFC prose (this RFC, the three amended RFCs above, and the frozen rejected steering-capability RFC, whose text records the proposal it declined); the catalog is regenerated and fresh. - The retargeted test pins source preservation on
steering/message; the suite is green.
Risks
None known: zero production listeners existed to migrate, and both live-notification needs (enqueue, drain) have surviving homes (agent/queued, session/event).