Each turn runs claude -p with stream-json in and out and maps its events onto pi's assistant message stream. A process that stops on tool calls is kept alive and continued when pi sends the results back, instead of replaying the whole transcript. API credentials are removed from the CLI environment so turns always bill to the signed-in subscription.
Chat records gain version (CURRENT_CHAT_VERSION), stamped by a single
writeChat choke point in the store; absence reads as v1 — existing files
migrate on their next write, no mass rewrite. The graph family (four JSONL
ledgers, sources.json, render-settings.json) shares one lazy sidecar,
graph/format.json; positions stays unstamped (rebuildable) and jobs stay
unstamped (transient).
Downgrade scenario ruled honest-refusal: records stamped newer than the
running build read as absent (chats, logged) or throw (graph family) — a
read-modify-write store never rewrites what it doesn't understand.
Golden fixtures stay the unstamped legacy shape on purpose (lazy v1 is
current-valid by design); the stamped write path is pinned by
tests/schema-stamps.test.ts. Reads never write — the golden byte-identical
pin holds.
Owner-manufactured teach master (chat_mv27rrra: compaction, subagent-abort,
every teach tool) + practice lifecycle (chat_mv293wv5: the full marker cycle
including the first-ever problem-dismissed), the real graph ledgers, five
jobs across the kind x status matrix, and settings. tests/golden-fixtures
reads all of it through the stores via the LH_DATA_DIR seam and pins the
fixture law: real data parses, flattens to a legal LLM wire, derives the
graph, covers every custom-marker kind, and reads never write.
Fixture law: an intentional format change updates these files in the same
commit; an unintentional one fails the suite.
Learner source files, on the teacher's own terms (nothing auto-injects):
- read tool (src/agent/tools/read.ts): pi-read port — path/offset/limit,
2000-line/50KB truncation with use-offset continuation notices, image
files (jpg/png/gif/webp/bmp) returned as native image content parts
(new LhToolImageResult escape hatch in lh-tool.ts). Always-on in both
the prober and teacher registries (user-decided 2026-09).
- pdf-reader sub-agent (JobKind 'pdf', toggleable, ack-and-steer): triage
via pdf_info (pdfjs text layer: per-page text/image/math-density),
targeted pdf_extract, regex pdf_search (hits count as consultation),
and pdf_render — pages painted by pdfjs onto a canvas shim in headless
Chrome (the pdfium viewer doesn't paint headless), screenshot fed back
image-in-the-loop (visual-maker idiom, providerSafePng applied). The
unread-finish gate bounces a zero-consultation brief once. Teacher gets
a text brief with page citations only; renders never leave the loop.
- MODELS.pdfReader = qwen/qwen3.8-flash (user override 2026-09-19: the
look-at-renders workload wants the vision-proven model; catalog listed
glm-5.3-flash as image-capable but qwen is the known-good daily driver).
- UI: PdfCompleteBadge + PdfBriefCard (steer-card, job-card), dispatch
card + activity-dock kind entries (type-forced, flagged for UI review).
- Prompts: 'Learner source files' section in teacher/30-jobs.md; read
line in prober/10-probe-doctrine.md. Doctrine rides tool descriptions
per the self-contained-tools principle.