Replaces the pre-pivot v0 scaffold doc (preserved in git history) with
the as-built spec: the five layers and their dependency directions, the
machine-enforced import law (four zones + the two documented-only
rules), ports/adapters and the two composition roots, the extraction
pipeline as sole graph writer (division of trust, merger invariants,
probe-attribution resolution, the v1 trigger seam), the pure read
channel, the turn seams, minimal observability, the testing strata, and
the deferred-with-links list. The doc states it describes the system,
not an intention — it changes with the commit that changes the system.
README reference updated (was: 'pre-pivot v0 scaffold — history only').
The knowledge graph's write channel is now the pivot's target
architecture (vision §1 construction):
- src/agent/subagents/extraction.ts — the pipeline factory
(createExtractionPipeline({ chatStore, graphStore, extractor?,
auditor? }); models env LH_EXTRACT_MODEL ?? LH_MODEL):
* transcriptView(): the compact view both LLM stages see — final plan
tree with node ids, conversation verbatim, QUIZ lines with outcomes,
mark_done lines; job tool parts are one-liners, plan ops fold into
the tree line.
* Extractor: transcript → SessionFindings (propositions incl.
misconceptions and prose-only supports edges, attribution for
UNTAGGED probes, all with verbatim evidence) via one zod-validated
submit_findings call.
* Auditor: transcript + findings → the verified subset + drops (the
faithfulness net) via submit_review.
- src/core/graph.ts — emitChat/foldStaleChats/replayFinalTree retire;
mergeFindings() replaces them as the pipeline's deterministic apply
stage: exact/alias identity resolution (one mapping line per (chat,
graph node)), edge dedupe, and event rebuild FROM THE TRANSCRIPT's tool
parts — kinds/timestamps/refs/notes deterministic, the LLM's only event
say being WHICH proposition an untagged probe tested (retroactive —
the vision's open question #3, resolved structurally: tagged events
resolve deterministically; attribution rescues untagged and
tagged-but-unmapped ones; unattributable land null + question text).
pendingQuizAnswers() is the trigger helper.
- Trigger (turn-service.ts triggerExtraction, replacing the old
foldTurnIntoGraph body): once a chat accumulates
EXTRACTION.everyNQuizAnswers (LH_EXTRACT_N, default 3) new answered
quizzes, fire the pipeline async — single-flight per chat, failure
checkpoints nothing and re-runs on the next trigger. Deliberately a v1
placeholder isolated in ONE seam, trigger-agnostic pipeline.
- GET /api/graph is now a pure read (foldStaleChats gone).
- NodeMapping.treeNodeId → sourceId (the mapping key is now the writer's
local proposition id — tree node when tree-derived); store strict-read
schema updated. Local ledger data regenerates through the pipeline.
- Tests: graph.test.ts rewritten around mergeFindings (identity,
attribution paths incl. ghost-rescue, idempotency, cross-session
provenance, trigger counting), graph-context.test.ts merge section
converted to findings-driven, NEW extraction.test.ts — transcriptView
units + the full pipeline with mock models (audit drops, failure
checkpoints nothing, single-flight). 195/195, tsc/eslint/build clean.
Probe attribution (vision open question): probes attach retroactively by
the extractor against the whole transcript; a pre-tree probe maps to a
proposition the tree only articulates later. Fuzzy/embedding merge
adjudication stays deferred (conservative exact/alias only).
The chat turn is now composed, not implemented, by chat-handler.ts:
- src/server/turn-service.ts: one named, error-contained seam per turn
responsibility — buildTeacherContext (W8 read channel), persistTurn
(canonical state write), spawnTurnJobs (async protocol kick-off),
foldTurnIntoGraph (session→graph consolidation; the extraction-pipeline
stage swaps this body behind the same seam). Each takes its deps
explicitly; failures log one [chat <id>] line and never touch the
response.
- chat-handler.ts wires: storage ports (stores), the job runner, the
teacher tools (ctx = chatId + injected ChatStore), and the services.
It no longer contains any logic beyond request validation.
Agent layer now receives dependencies instead of importing them — a new
lint zone enforces it (src/agent never imports src/server or src/store;
verified to fire both ways):
- runner.ts: createJobRunner({ chatStore, jobStore }) factory returning
the spawn hook + the three job runners; the model-override test seam
stays module-level. Bodies otherwise verbatim.
- plan tools: persist through the ctx-injected ChatStore
(TeacherToolContext = { chatId, chatStore }).
- teacher-agent's dependency-free default registry is now the true
client-side set: questionTools + jobTools (jobTools was ctx-parameter-
shaped but never used its ctx — now honestly context-free). Production
always passes createTeacherTools({ chatId, chatStore }); tests that
drive a bare mock model get the client-side set unchanged.
Zero behavior change: tsc clean, 190/190 tests, eslint clean, production
build clean. Tests inject the same fs ports the chat-handler does.
Per-entity semantic ports (src/core/ports.ts), one adapter family
(src/store/*, fs JSON/JSONL), exactly one composition point
(src/server/stores.ts). Dependency direction is now machine-checked:
adapters implement core interfaces; core never imports an adapter.
The inversion:
- core/graph.ts (emitChat/getGraph/graphSnapshot/foldStaleChats) is now
pure — it takes the storage ports as explicit parameters (GraphDeps).
No store imports; newGraphNodeId is local; node id format unchanged.
- core/graph-context.ts buildGraphContext() no longer defaults to the
live ledgers: the chat-handler hands in getGraph(graphStore) per turn.
- store adapters export exactly one object each implementing their port
(chatStore/graphStore/jobStore); bodies otherwise verbatim.
NodeMapping + SessionCheckpoint moved store/graph -> core/contracts
(they ARE contract shapes); CreateJobInit/JobPatch live in ports.
- titleFromPrompt moved store/chats -> core/contracts (pure helper,
planNodeStatus precedent). Store modules now contain persistence only.
- server/stores.ts is the composition root; server/{chats,graph,jobs}.ts
and chat-handler wire from it; agent (plan tools, sub-agent runner)
call the port objects. The shell surface (@/src/server exports) is
unchanged.
Lint law extended: the whole of src/core is now a purity zone (was a
file glob with a graph/graph-context exemption). Verified it fires on
core->store imports; tsc clean, 190/190 tests, eslint clean, prod build
clean (prerender 6/6). Tests pass deps explicitly — graph.test uses the
same fs-adapter pair stores.ts wires in production; graph-context.test
keeps its in-memory ledgers as a GraphStore implementation.
Delete src/extract/ (pi-session normalize/extract/merge stubs), src/ledger.ts,
src/schema.ts, src/derive.ts, src/queries/, src/cli.ts (npm run ingest/graph/
what-next), data/legacy-graph/, data/agent/ (pi agentDir vestige), and their
config.ts/package.json references.
The retroactive-bootstrap goal is dropped: the live chat store (AI SDK
UIMessages) is the only session format now, and the old pi JSONLs in
data/sessions/ stay on disk, inert. contracts.ts is the single schema.
The old README documented the pre-pivot pi/Fastify/Vite scaffold (npm run
teach, doctor scripts, Fastify+WS server, extensions/) — all removed in the
pivot to standalone Next.js + Vercel AI SDK. New README covers the current
commands, env vars, embedded architecture diagram, key mechanisms
(client-side question tools, plan tree, async sub-agent protocol, live
graph emission), the dormant legacy scaffold, testing, and lineage.
Also commits the pending next-env.d.ts regeneration.
Root causes of the v1 browser bugs (all fixed + covered by deterministic tests):
- duplicated messages: per-socket snapshot + global broadcast marking raced;
replaced with a single append-only entry log (exactly-once per socket,
structurally) — covered by tests/server.test.ts
- delayed/missing echo of own messages: optimistic append with sending/failed
status, reconciled by text when the real entry arrives
- no thinking shown: thinking deltas streamed live (kind: thinking) and
persisted in assistant entries so they survive reloads
- ask answers graded as wrong: AnsweredCard no longer applies quiz grading to
ask answers (no ✓/✗, no verdict)
- broken option selection: native radio/checkbox inputs fighting React state
replaced with button-based options (single source of truth, one-click select)
- no URLs: History API routing — / home, /s/<file> per session (deep links,
refresh, back button); session view resumes its file on mount
- lost connection = dead UI: exponential-backoff reconnect with full resync
- stick-to-bottom transcript with jump-to-latest pill
Server: startServer() with injectable runtime factory (scripted model in
tests); createSession returns file for routing; scripted model gained thinking
turns. 51 deterministic tests green.
Amos