- Every session starts with the learner's knowledge graph as base
context (precision probing); selection problem noted: pedagogical
relevance != semantic closeness (structural neighborhood, diagnostic
hotspots, frontier strip); strategies to tune on data.
- Sub-agent architecture: async background workers with live activity
indicators; demo-builder TESTS code headlessly; visual-maker verifies
by looking (port of vault svg-maker); mermaid needs no sub-agent;
researcher tool for fact verification (port of pi web-search/web-fetch
+ interactive-subagents researcher prompt).
- Not-a-chat presentation principle marked LOW PRIORITY per user.
Margin model flaws (user feedback): fragment placement needs unreliable
routing; scattering kills the receipt moment and chronology; session
value is in the moment, revision is rare, HTML export deprioritized.
Evolved model: one chronological spine; learner blocks are intact typed
'interjection' cards; teacher replies as woven Q&A interludes
(quote-then-answer); anchoring is a link overlay (backlinks), margins
demoted to a computed view. Chat-ness dies by type asymmetry, not
relocation.
Asymmetry of artifact: the teacher writes the document (whiteboard), the
learner writes in the margins (voice/floor). Bubbles die; the unit is the
block; chronology yields to tree structure; Q&A becomes document
furniture; the composer becomes a response field. Presentation-layer
change only — the interaction model stays conversational.
Captures 2026-08-22 decisions: hybrid live-emission + consolidation graph
construction (reversing the vault doc's teacher-untouched rule), one
substrate merged across sessions, structured plan-tree tools (mermaid
demoted to ad-hoc), probe/teach phase separation with collapsed teach
checks, right-panel tree view, LaTeX delimiter switch plan, and a
dependency-ordered roadmap.
Clicking the collapsed bar set expanded=true and started a smooth
scrollToBottom — but the scroll position was still legitimately inside
the collapse zone (that's why the bar was showing), so the hysteresis
listener re-collapsed the dock on the very next scroll event, then
re-opened it when the scroll arrived: open → snap shut → reopen.
The machine had no notion of intent. Now the bar click sets an
expandIntent flag that suppresses the collapse branch; it clears when
the scrollToBottom promise settles (completion or interruption) or after
a 2s safety net, so a user yanking the scroll away mid-reveal collapses
the dock again instead of wedging it open.
Verified live: click = exactly one transition (bar→open at ~26ms, stays
open, lands at d=1); collapse still healthy afterward; mid-reveal
interrupt re-collapses within ~300ms.
- Chat now remounts per session (key={chat.id}): fresh StickToBottom,
fresh DockOverlay (no cross-session morph from the previous shell
height), fresh useChat.
- Conversation initial="instant" (was "smooth"): the mount scroll to
bottom is a jump, not a slide.
- DockOverlay skips the pending-question scroll/expand effect for the
session's INITIAL pending question (dock starts expanded; the initial
scroll positions us) — previously it fired a second smooth
scrollToBottom right after the library's initial scroll (the visible
'pause, then the quiz pops and pushes everything up').
- The dock-variant fade/rise no longer plays for the session's opening
variant; reserved for mid-session transitions.
Verified live: client-side switch settles at d=1px from the bottom within
one frame of content swap, dock open from the first frame, both
directions (quiz session, plain session).
- Oscillation fix: collapsing the dock frees ~Δpx of flow height; within
Δ of the bottom the browser clamps scrollTop to the new max, landing
the learner AT the bottom, which re-expanded the dock → loop. Now a
hysteresis state machine on the scroller's scroll events: collapse only
when distance-from-bottom > Δ+64 (strictly clamp-proof), expand only
within 16px of the bottom. ~370px dead band; exactly one transition per
direction verified live. Heights measured live per question.
- Reaching the bottom re-expands the dock AND scrolls to reveal it fully
(previously it grew over the content and left you short of the bottom).
- Streaming follow fixed: ConversationContent had h-full, so the observed
content box never grew and use-stick-to-bottom's ResizeObserver never
fired — no auto-scroll during streaming. min-h-full restores growth.
Verified: distance-from-bottom ≤70px transient during a 25s stream,
settles at 1px.
- Animation: the blob's shell morphs height (WAAPI, 180ms) on every
variant change — chat ↔ question ↔ collapsed bar — plus a quick
fade/rise (160ms) on the swapped content. Gotcha pinned in code: never
measure the shell while a morph is in flight (getBoundingClientRect
reads the ANIMATED value and corrupts the next morph's start height);
cancel running morphs before measuring, refresh settled height only
when no morph is running.
- Gradient-over-scrollbar fixed structurally: the dock is no longer an
absolute overlay on the conversation root — it's sticky bottom-0 INSIDE
the scroller (in flow). The transcript scrolls fully clear of the dock,
the fade never touches the scrollbar lane, and the pb-hack clearances
are gone.
- New question while at the bottom scrolls to reveal the dock; scrolled
up → collapsed bar, no yank.
- Thin dark native scrollbar app-wide (8px webkit + scrollbar-width:thin,
dark thumb, transparent track). Note: use-stick-to-bottom sets
scrollbar-gutter: stable both-edges on its scroller — the lane is
outside the content flow by design.
- 'Writing a question…' transcript shimmer while a tool call streams its
input (same slot as 'Thinking…'). Protocol pinned by a test asserting
tool-input-start precedes tool-input-available; scripted mock now
streams tool input as deltas like real providers do. (OpenRouter/
Anthropic often delivers the whole input in ONE delta — then the dock
appears instantly and no indicator is needed or shown.)
Verified live: grow 54→349px and shrink 349→54px fire with correct
from/to; collapse/expand intact; gradient stops before the gutter;
Thinking… observed in-page; 58/58 tests.
- A pending quiz/ask now REPLACES the chat composer: one persistent
rounded-2xl shell in the transcript overlay swaps contents (composer ↔
question ↔ collapsed bar), never remounting — the structure a future
grow-morph animation needs.
- Unified bottom row inside the question: the note field (select modes),
the answer field (text-mode asks), or the Other text — one field, one
'Submit answer' button, Enter submits.
- Collapse on scroll: uses useStickToBottomContext — scroll up and the
dock folds to a slim bar (kind chip + LaTeX-flattened question teaser +
'tap to answer'); click scrolls to bottom and re-expands. The expanded
form stays mounted-hidden so a half-made selection survives.
- Pending/streaming tool parts no longer render inline; answered parts
land in the transcript as graded cards on submit. Question generation
shows a shimmer in the shell.
- Composer back to pure chat (no mode machinery); quiz-card.tsx and the
pendingText/registerSubmit bridge deleted; render tests re-pointed at
the dock (wrapped in StickToBottom).
Verified live: docked quiz submit (note+selection), ask-text Enter
submit, collapse/expand with selection survival, bar teaser text.
Sidebar (replaces the modal drawer):
- Inline, toggleable, no backdrop/focus theft — can stay open while working
- Open state persists across pages (provider in root layout) and reloads
(localStorage; starts closed server-side to avoid hydration mismatch,
stored value applied post-mount; default open on first run)
- Hamburger in page headers only when closed; close button in sidebar header
Floating composer blob (per reference screenshot):
- Floats over the transcript (absolute overlay), persists at bottom while
scrolling, content fades behind it (gradient mask); pb-44 scroll clearance
- Concentric corner radii: blob rounded-2xl(16px) − p-1.5(6px) = send
rounded-[10px] = 25% of the 40px button; CornerDownLeft icon per reference
- Stop moved from header into the blob (busy → square icon)
- prompt-input.tsx + 7 orphan ui files pruned (attachments/command palette
unused); hand-rolled Composer is ~100 lines and render-tested
Pending-question morph (one text field on screen, never two):
- Quiz/ask-select pending → blob becomes the note field (send hidden, hint
line above); card's internal note input removed; Submit consumes it
- Ask free-text pending → blob becomes the answer field; its send submits
via the card's registered submit api (ref bridge); Enter works
- Chat owns the single text state; card clears it on submit
- canSend for answer mode mirrors the card predicate directly — reading the
ref during render lagged one commit (found in browser testing)
Widths: one shared column (max-w-3xl + px-4) for transcript, cards, and
composer — all three measured pixel-identical (left 416, width 736).
Assistant Message max-w-full/MessageContent w-full (was max-w-[95%]/w-fit —
the 'cards are a bit shorter' bug).
User messages render plain text again — no math pipeline on learner-authored
text (currency hazard accepted for the model only, guarded by the prompt).
Tests: 58 pass (5 new composer pins; card tests updated to controlled
props). Verified live: note flow, answer flow, sidebar persistence, float,
fade, zero console errors — plus the live model spontaneously honoring the
$ currency escape contract in a continuation.
Layout:
- Home = knowledge-graph placeholder (main view) with new-session input
docked below; session list moved out of home into a hamburger drawer
- SessionDrawer: slide-over session navigation (backdrop/ESC close, active
highlight, fetches /api/chats on open) on both home and chat headers
- Chat header loses the back button — the drawer is the navigation
Math (inline $ was silently not rendering):
- @streamdown/math defaults singleDollarTextMath:false — now
createMathPlugin({ singleDollarTextMath: true }) in message + reasoning
- katex.min.css imported in layout (streamdown does not inject plugin
styles; display math only looked right via browser MathML fallback)
- QuizCard/AnsweredCard route question/options/explanation through
MessageResponse; user chat bubbles render markdown+math too
- Currency hazard: micromark-extension-math@3.1 lacks pandoc's
closing-digit rule, so bare '$5 and $10' parses as math — defense is at
the source: system prompt now instructs escaped \$5 / 'USD' for money
Hydration fix (React #418):
- QuizCard shuffled options with Math.random() — server/client orders
diverged. shuffleOptions now takes an injectable RNG; QuizCard passes
seededRandom(toolCallId) (mulberry32/FNV-1a in question-core). Same
question → same stable order across reloads; still varies per question.
Tests: 53 pass (5 new math-rendering pins incl. fenced-vs-one-line $$
behavior and the escaped-currency contract). tsc + next build clean.
Verified live in browser: inline/display math in text + cards, drawer
open/navigate/active-highlight/ESC, no console errors, no font 404s.
The teaching agent no longer runs on pi. Stack:
- ToolLoopAgent (ai@7) + OpenRouter (OPENROUTER_API_KEY), model via LH_MODEL,
default anthropic/claude-sonnet-4.5 with reasoning tokens
- quiz/ask_user_question = client-side tools (no server execute): the call
lands as a typed tool part in input-available state; the card grades via
src/core/question-core.ts; addToolOutput sends the verdict; the teacher's
reaction continues the same assistant message
- resume-mid-quiz is free: the pending tool part persists in the transcript
- persistence: one JSON per chat (data/chats/), full UIMessage transcripts,
saved onFinish (also on abort)
- UI: AI Elements (owned copy-paste components, pruned to the five in use)
+ button-based QuizCard/AnsweredCard (ask answers never graded)
- pi fully removed: TUI, extensions, Fastify+WS server, bridge, custom
protocol all deleted (recoverable from git history)
- tests: question-core units carry over; chat-flow integration drives
handleChatRequest with MockLanguageModelV4 (48 tests, zero tokens);
render smoke tests guard the cards (renderToStaticMarkup)
Carried over unchanged: teacher system prompt, question-core, schema/
ledger/derive/extract pipeline, data model.
- Markdown.tsx never passed text as children to ReactMarkdown (valid JSX,
compiled clean, rendered nothing) — the 'thinking shows, text doesn't' bug
- toolResult entries (quiz/ask dispatch instructions for the LLM) leaked
into the transcript as visible text; now never rendered
- render smoke tests (renderToStaticMarkup, no DOM): pin markdown content,
KaTeX, button-based quiz options, ask answers not graded, toolResult and
[Quiz answer] hiding — negative-tested against the actual bugs
- React default import in all .tsx: tsx test runner uses classic JSX
transform (ignores tsconfig jsx option), Vite uses automatic runtime;
explicit import works under both
- katex css moved to main.tsx (tests can't import css)
- verified live in browser: all assistant messages render, ask card has no
grading marks, pending quiz re-arms on resume
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