Root cause (postmortem, verified live): Chromium caps 6 concurrent
HTTP/1.1 connections per origin. Every running turn pinned slots for
its whole life — the POST /api/chat response stream plus a reattach
GET stream per visit that never closed on navigate-away — so two
concurrent thinking sessions starved navigation RSC fetches in the
browser queue (147s measured) until the turns settled. Server was
exonerated (3ms curls during the freeze); main thread idle throughout.
- COMPACTION LAW + WIRE DIET (ui-stream): store the states, not the
chunks — replace-in-place snapshot retention keyed by updateSlots,
~100ms coalesced latest-wins fan-out, slim wire drops pi's duplicate
assistantMessageEvent payload.
- DIET B: POST /api/chat acks and closes ({ok:true}) — the turn wire
is GET /stream for everyone, submitter included; send() reattaches
via refetch-first resumeStream(true).
- DIET A: unmount cleanup calls model.stop() — navigating away aborts
the view connection (turns are server-side background objects).
- Answer-flicker fix: resumeStream's eager tail clear moved off the
refetch path (the refetch swaps base+tail atomically; clean-slate
guard restored on refetch failure) — the optimistic answer card
survives refetch latency (1.7s stalls measured on dev).
- Tests converted to the ack contract (drainTurn/drainRunning helpers,
dietFetch mock) + a pin that the POST body reads while the turn runs.
Gates: 1489/1489, typecheck, lint. Live: dual streaming sessions,
navigations 335-648ms, in-page settings 19ms (was 147s).
DeepSeek via OpenRouter returns tool-call ids that reset every response —
a one-call-per-turn session names every call call_0. Everything keys on
toolCallId (the fold's call↔result join, the pending gate, answer
routing, the option-shuffle seed), so the Lacan session corrupted: the
quiz answer overwrote the ask card, the ask question vanished, and the
order scrambled. Record itself was always intact.
- src/server/pi/call-ids.ts (new): ToolCallIdUniquifier at the wire
boundary — colliding ids remint once (orig~2, ~3…), the same mints at
settlement; tables key by message OBJECT IDENTITY (streaming messages
carry no ids; the message_end object is reference-identical to the
state object). History never rewrites; providers see paired ids, which
is protocol-legal (pi synthesizes ids for providers that send none).
- ui-stream: runPiTurn remaps events + settles through the uniquifier
(spec.usedToolCallIds, seeded by chat-handler from the record).
- view.ts: findToolPart scans newest-first — pre-fix duplicate-id
records (the existing Lacan session) heal on next render.
- tests: 9 unit pins (call-ids.test.ts) + the two-call_0 e2e (chat-flow):
ask answered as ask, quiz as quiz, ids unique in the record.
TWO owner-reported bugs from the live red-circle session
(chat_muhpyoll_27305e23), both investigated to root cause first:
1. THINKING BLOCKS UNDER THE MESSAGE. GLM emits trailing reasoning
tokens, so the persisted content lands [text, thinking] (4 of the 6
thinking-bearing messages from [21] on in that session) - and the
view canon presented arrival order verbatim, rendering the reasoning
UNDER its own message. Fix: projectView stable-partitions each
assistant message - reasoning parts first (their own order kept),
then text/tool parts. Owner ruling 2026-09-26: the reasoning belongs
above, always. Covers live partials and settled records alike (one
projection canon). NOT addressed (owner ruling): the plan_tools
"missing" claim in the same session - wire-verified 11 tools incl.
plan_init; GLM confabulation, no mitigation wanted.
2. DOCK CARDS LINGERING AFTER DELIVERY. /api/activity lists jobs with
status "running", and the status flipped only in settleSteers at the
DELIVERING TURN'S onFinish - so a subagent whose card was already
visible in the transcript (marker injected mid-run) stayed in the
background dock until the teacher finished teaching. Fix: flip the
job at the moment the result reaches the learner - noteSteerVisible
(jobs.ts) called from BOTH visibility seams: the marker's message_end
wire event (live steer injection, ui-stream) and the write-ahead
persist (the wake's input appends, chat-handler). finalizeJob is
idempotent; settleSteers/runner-200 re-run it as a no-op, and the
registry's delivery promise still settles exactly as before.
Tests: 1001/1001 - view-canon hoist pin (trailing [text, think, call]
projects reasoning-first; think-first unchanged), noteSteerVisible unit
pin (flip at the seam, idempotent, handoff no-op), and the mid-run
steering e2e now holds the turn open past the injection and pins the
job flipping done at the marker's message_end WHILE the turn still
streams. Live-verified read-only on the owner's server: the original
session reloads with every reasoning trigger above its message.
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.
Owner ruling 2026-09-25. runPiTurn executes a turn decoupled from any HTTP
response: an unbounded memory-only event log (finite by construction; the
30-min liveness TTL bounds the pathological case) plus a subscriber set.
The POST /api/chat stream and the new GET /api/chats/[id]/stream are both
subscribers — identical SSE dialect; late subscribers get FULL replay
(starting at the start chunk) then live until finish + [DONE]. A view
cancelling (reload, navigate) now detaches ONLY — never aborts the turn.
The remote kill is the abort channel: POST /api/activity/abort gains
kind: "turn" (id = chatId; not_running 409 like jobs); handle.abort sets
sawAbort + agent.abort(), every subscriber closes cleanly, the partial
persists through the usual settle (onFinish runs once, then endTurn,
then unregisterTurn LAST so a view that finds nothing finds the record
current). No running turn on reattach: the cheap terminal — one
{"type":"turn-settled"} event + [DONE] (settledTurnResponse).
The live smoke caught what the unit suite had masked: the agent_end
close() had been left behind in the restructure — ReferenceError every
turn, steered into the error path; fixed and pinned (clean turns must
never emit an error chunk; finishReason stop present).
The owner's zero-configuration ruling (2026-09-23): nothing configures
the graph beyond chat models. The prior-knowledge injection — its budget
dial, its runner, its marker part, its dock/dispatch entries — is
removed across all bands; the prober now reads the learner's persistent
knowledge map on demand through two gated tools instead:
- list_sessions: every birth session, names + kinds + counts + dates
(graphSessionIndex, Platform's core seam)
- list_propositions(session): what was born there + the session's own
latest understanding level + that evaluation's date
(graphSessionPropositions) — names/levels/dating ONLY, no statement
text (owner ruling: the map's organization is the prober's business,
its prose is not)
Registered via createProberTools when chat-handler passes graphStore
(the graphToolsEnabled gate decided server-side, per-turn fresh); the
prober doctrine gains the map-review nudge at session start.
Also: runner's JobKind special-casing collapses (KIND_ROLE/KIND_RUNNERS
are plain records again), semantic-clusters.ts dies with its test, the
embedder dep's doc tells the wave-7 stub story, and ports.ts's
readClusterLabels/readNamingRuns surface stays untouched for Platform's
ledger-port interlude.
848/848 tests, typecheck/lint/build green.
One shot per chat, fired at the first turn's onFinish: the session's
topic (its only typed message) is embedded as an EmbeddingGemma retrieval
query; the semantically closest graph propositions are selected under the
session's token budget (pure budget, no similarity threshold — the
decided doctrine) and delivered as a marker-only steer through the wake
pipeline, queuing behind pending questions like every sub-agent result.
- contracts: ChatSettings.graphContextTokens (default 1024, max 4096,
step 128, 0 = off); GraphContextData + graphContextText; the
graph-context JobKind + buildGraphContextSteer (id steer_ctx_<chatId>)
- core/graph-context.ts: brute-force cosine top-K, greedy chars/4 fill
under budget, most-recent UnderstandingLevel fold, count cap 64,
parse-don't-cast at the marker seam
- server: embedQuery (role-asymmetric query format, same warm singleton
— vector-space parity by construction); the runner (startGraphContext-
Injection one-shot gates; runGraphContextJob validates ledger parity);
wake branches (chatIdOf/jobIdOf, finalizeJob done, recoverStaleJobs
re-deliver or contextRespawn); abortJob kills context jobs SILENTLY
(nothing was promised in the lesson); turn-service trigger seam
- adapter: data-graph-context flattens to the canonical block (malformed
parts have no model face)
- UI: the budget slider (home dock + /chat/new draft, the session-data
strip); the quiet SystemLine "~537 · 10 propositions"; dock kind
"Knowledge context"; model-picker PUT now spreads settings (a model
pick can no longer clear the sibling override)
Live-smoked end to end on the real embedder + real GLM: seeded ledger
(10 propositions), session on "modal logic: possible worlds and the
necessity box" — job in the dock, queued behind the prober's question,
delivered on the answer, SystemLine in the transcript, wake turn reads
the block and continues the probe. Gates: tsc, lint, 459/459, build.
The custom-message scheme (user-decided 2026-09-12): system-authored
user-role messages are NOT human messages — they carry marker data parts
only, the adapter owns their model-facing wording, and the UI renders
them under control. Nothing fake is ever persisted as human speech.
The inventory (all migrated):
- probe→teacher handoff wake: was a text-bearing user message rendering
as a fake user bubble; now data-probe-handoff marker-only — the
adapter flattens it to HANDOFF_TEXT (core/contracts/chat.ts), the UI
renders a quiet 'Preparing your plan…' system line.
- plan accept/decline: was boilerplate text ('The plan is accepted…',
'I'd like the plan revised…') masquerading as learner speech — the
decline wasn't even marked; now data-verdict {accepted, at} on its own
message, adapter flattens to verdictText(), UI renders the quiet
verdict marker ('✓ Plan accepted' / '↻ Plan revision requested').
sendVerdict sends TWO REAL MESSAGES when the learner typed a note
(the note as a genuine user message, then the verdict) in ONE turn
via setMessages + sendMessage() — no 409 dance, no double teacher turn.
- sub-agent steers: the abort steer gains its data-subagent-aborted
marker part; the UI keys steer rendering off PARTS (artifact/aborted),
not metadata — metadata stays as pump mechanics only.
- record-adapter: systemTextOf() flattens marker-only messages; steers
keep their text (payload — briefs are content, not boilerplate).
phases.ts: plan→teach advances on data-verdict{accepted:true} only;
learner text alone can never sanction teaching (pinned). data-plan-
accepted retired, no back-compat (user-decided: wiped-data doctrine).
Pinned: record-adapter.test.ts (verdict/handoff flattening, note+verdict
order, steer payload kept, UI-only parts skipped), phases.test.ts
(verdict marker semantics, out-of-order, text-never-fakes), jobs.test.ts
(abort marker part), demos.test.tsx (badge renders off the part, not
metadata).
Live GLM smoke (disposable driver, deleted): probe→conclude→wake→plan→
decline-with-note (revised, still plan)→accept-with-note (teach) — ALL
CHECKS PASS, including marker-only handoff/verdict on the wire and zero
fake human speech in the transcript.
Gates: tsc, lint, build, 335/335.
Live crash (modal-realism session): GLM double-encoded the quiz options
array as a JSON STRING inside the tool-call arguments. The bridge emitted
tool-input-available at toolcall_end — BEFORE validation runs — so the
client briefly saw the malformed quiz as a pending question and the dock
crashed in normalizeOptions ((string).map). The later tool-input-error
chunk could not revive the tree.
The old SDK gated this with InvalidToolInputError: validation ran before
the input-available chunk. The bridge now holds the part in
input-streaming until tool_execution_end and only then emits
tool-input-available (clean) or tool-input-error (invalid, structural
JSON Schema failure or the zod re-run inside execute).
Server-side behavior was already correct (the record shows the error
part + a successful model retry) — this is purely the wire-ordering hole.
Pinned in chat-flow.test.ts: the refinement-layer retry (correctAnswer
mismatch) and the exact live structural shape (string options) both
assert the invalid call never becomes input-available on the wire.
Gates: tsc, lint, build, 306/306.
The Vercel AI SDK survives only as Band D (useChat client + UIMessage
record types); @openrouter/ai-sdk-provider is uninstalled.
- src/agent/models.ts: PiEngine {model, streamFn} via createModels +
openrouterProvider subpath; thinkingLevelFor maps config effort none->off
- src/agent/lh-tool.ts: neutral LhTool (zod authoring, optional execute,
clientQuestion flag); toPiTool converts via z.toJSONSchema and re-runs
zod inside execute so refinements ride the error-result retry path
- src/server/pi/record-adapter.ts: UIMessage records -> pi Messages
(dangling tool calls get synthesized interrupted results)
- src/server/pi/ui-stream.ts: SSE bridge emitting AI-SDK-shaped chunks so
the useChat client parses unchanged (continuation id rule, question
tools never emit output, tool-input-error for bad authoring)
- teacher-agent.ts: stateless per-turn pi Agents; shouldStopAfterTurn
stops only when every question-tool call resolved cleanly (errors retry)
- chat-handler.ts: buildAgent(outgoing) factory seam (stateless doctrine);
assertValidUiMessages owns the retired SDK validation gate
- sub-agents via shared runSubagent (pi-run.ts); extraction stages stop
after a clean submit; visual-maker keeps its hand-rolled loop over
direct streamSimple calls; aborted model calls bill no usage
- tests: all model seams ported to pi-ai faux provider (scripted
FauxResponseSteps, agent factories); handleChatRequest second param
is now an agent factory
Gates: tsc, lint, build, 305/305. Live GLM smoke (disposable driver,
deleted): prober streaming + persistence, question seam, turn-2
continuation same message id, per-turn real token usage - ALL PASS.
Data wiped at the pivot (chats/graph/jobs, .gitkeeps kept).