The native shapes beneath the practice tools (owner design 2026-10-04):
- activeProblemOf — the conclude-before-next-problem gate's fold (a
conclude call OR a dismissal marker deactivates; the pose-time ack
never does — nudges keep the card up).
- The thinking input: {problemCallId, commit, text} → practice-thinking
marker; the label (THINKING_HINT/COMMIT_LABEL, single-sourced in
contracts) is the only register difference the model sees.
- Ask-style problem dismissal: silent route appends the UI-only marker;
the user's NEXT input prepends the synthesized conclude pair (call
outcome:'dismissed' + shared ack) so the agent reads the discard in
its own vocabulary and the slot frees.
- toLlmMessages: dismissal marker filtered; pair passes natively.
STEERING, NOT FOLLOW-UPS — pi-agent-core's two rails, used deliberately:
agent.steer() injects at the next response boundary INSIDE the live run
(one logical turn, the model changes course); followUp() would only extend
an ended run — not built. The same rail job markers already ride
(steeringMode 'all', the 2026-09-26 doctrine).
- POST /api/chats/[id]/steer: 404/400 honest guards; no live turn → 409
and the client silently falls back to a plain text send (the settle
race); live → steerLiveChat hands the message to the live agent's
steering queue AND parks it in the userSteers registry — the stranding
safety net. A steer stranded behind a question termination or abort
stays parked and rides the chat's NEXT run (handOffEligible), the same
deliver-or-requeue lifecycle as job markers. Reconciliation at settle:
delivered ids drop (reconcileUserSteers).
- Client: steer(text) queues + POSTs without flipping any turn state;
the drain's verbatim message events upsert the real user card by the
client-minted id (steer_<localid>) and the indicator fold drops the
line. canSend no longer gates on turnInFlight — Enter mid-turn steers;
Enter with an empty composer still stops; the square button stays Stop.
- The queued-steer indicator (owner spec): quiet one-liners above the
composer shell — right-aligned to where its corner rounding starts,
truncated with an ellipsis, fixed max width, ~half opacity, no
background, no container. Tunable later.
- Verified from pi-agent-core source: steering drains per completed turn
inside the loop; injected messages emit message_start/end verbatim;
finishTurn {action:'end'} (our question stopper) exits BEFORE the
steering poll — hence the registry.
Live test finding: answer A then dismiss B woke the agent — the continuation
fold treated a mixed [answered, dismissed] trailing batch as 'reaction owed'
(all-dismissed rule only). Dismiss A then answer B and dismiss-both were
already correct.
The law now: the trailing batch's LAST resolution decides. Ending on a
dismissal = the user signaled stop — no wake, the answers' reactions ride the
next plain message. Ending on a real answer = the reaction is owed. One law
with the pump's pause (endsInDismissal reads the same last result), so
continuation, delivery-holding, and the pause can never disagree. The wrong
pin ('a real answer in the batch still demands the reaction') flipped.
- {type:"dismiss"} input event: parse + pure appends with the answer-event
orphan discipline (dangling-call 400, kind match, answer must be dismissed)
- POST /api/chats/[id]/dismiss: the no-turn composition — write-ahead append,
409 while a turn runs, emits record-changed (new bus word; idle views sync)
- needsContinuation: an all-dismissed trailing batch demands nothing;
endsInDismissal = the derived pause predicate (tail-based, no latch)
- wake pipeline: while the record ends in a dismissal the pump holds every
delivery in the steer queue — the user's next send is the wake (until the
text-turn steer claim lands, settlement re-pump delivers right after it)
- session-core.dismissQuestion: optimistic skipped card + silent POST;
chat.tsx confirmAbort question-mode swaps submitAnswer for it; ESC-abort
popup everywhere (AbortTurnDialog) with popup-Esc claimed via state gate
- parallel question calls dismiss call-by-call (results bind by id)
The Accept/Decline verdict gate is gone (owner ruling 2026-09-26):
presenting the plan ends the teacher's turn; the learner's next message
is a natural reply. Teaching begins at the first quiz call tagged with a
nodeId (probe quizzes carry none) — both folds (view phaseAt3, native
phaseAt3Lh) advance on the call itself, and the teach divider renders
before that whole assistant block. No backwards compat: verdict markers,
the verdict input event, optimistic appends, composer buttons, and
projection all deleted; prompts and docs rewritten to the natural flow.
Server: ui-stream.ts is verbatim pi AgentEvent passthrough (SSE data
lines + [DONE]); only app-level events are the loop-level error and
turn-settled terminal; onError carries raw provider text (owner ruling).
Client: useChat + the AI-SDK transport replaced by components/session-core.ts
(SessionModel: 409 identity-retry, optimistic c_ appends, absorbed()
adoption, needsContinuation, shared consume for POST + reattach) and the
session.ts hook; the golden-master grouping canon moved client-side into
core/view.ts (projectView); scanners read the native record (phaseAt3Lh,
danglingQuestionOf, graph toolParts, plan-blocks, runner, extraction).
Coverage: the native message is the unit (fork 3) with the call+result
inseparability bond rule; view-line-less messages (markers, error
results) are invisible to coverage and never checkpointed.
Deletes: chat-transport, projection, ui-message, their tests (ported to
tests/session-core.test.ts), and the ai + @ai-sdk/react dependencies —
the Vercel SDK is fully out of the tree. Wire pins in chat-flow rewritten
onto the AgentEvent dialect (eventsOf parser).
Gates: tsc clean, 994/994 tests, eslint clean, build green; live smoke
on PORT=3004 (verbatim wire → native record).
The chat record is now pi-native agent history (LhMessage[]), the AI SDK's
UIMessage transcript contract is gone from the server, and every client turn
arrives as ONE explicit input event.
Core (new):
- src/core/native-messages.ts — the LhMessage taxonomy (user/assistant/
toolResult + lhMarker customs: verdict, probe-handoff, subagent-steer,
subagent-abort, plan-block), constructors, and toLlmMessages — the single
model-facing seam (convertToLlm): strips ids, flattens markers to user
text, drops UI-only plan-blocks, synthesizes INTERRUPTED results for
dangling aborted calls, never throws.
- src/core/projection.ts — projectNative: the one-way native → UIMessage
projection (consecutive assistant+toolResult runs group into one
assistant view message; toolResults attach backward by toolCallId;
markers project to data parts; plan-blocks splice after the last
successful plan_init). Every existing consumer reads through it.
- src/core/input-events.ts — the ChatInput union (text/answer/verdict/
continue), parseChatInput validation, and inputAppends (answer targets
the dangling question call or 400s; verdict = optional note user
message + native verdict marker).
Server:
- chat-handler.ts — the turn root takes {chatId, input}; write-ahead
persists input appends + claimed steers before the turn; claimSteers
coalesces the whole queue with the handler's steerDelivered filter as
the dedupe seam; teacher-vs-prober branch on hasProbeDone.
- turn-service.ts — persistTurn stamps ids, drops clean question
placeholder toolResults (the record ends at the unanswered call),
emits plan-block markers idempotently (plan-blocks.ts rewrite), and
persists abort partials.
- ui-stream.ts — PiTurnSpec takes the native base; the wire dialect is
unchanged. jobs.ts steers are native markers (steer_<jobId> dedup ids);
waitForIdle reads danglingQuestionOf. teacher-agent.ts wires
convertToLlm: toLlmMessages. record-adapter.ts DELETED wholesale.
- GET /api/chats/[id] serves messages: projectNative(record.messages).
Client:
- chat-transport.ts — the 409 retry is IDENTITY (re-POST the same event
body after the turn settles — the event was never persisted
pre-acceptance; the merge logic is gone). The transport consumes the
stashed input event via prepareSendMessagesRequest and throws loudly on
a missing stash.
- chat.tsx — every send call site stashes exactly one ChatInput event
(text, answer, verdict, continue) before invoking the SDK send.
Tests: full native migration (chat-flow rewritten to input events and
native record pins; jobs/extraction/demos/graph/usage/plan-blocks/
probe-done/reattach-transport converted; record-adapter.test.ts deleted;
chat-transport tests pin the identity retry). 982/982, typecheck, lint,
build all green.