Four call sites did `s[:limit] + "…"`. Both halves are byte operations:
len() counts bytes and a slice cuts bytes. On Swedish text — å ä ö are
two bytes, an em dash three — the cut lands mid-character and leaves an
orphaned lead byte, producing invalid UTF-8.
It failed loudly in exactly one place: wiki/index.md is written raw to
disk, where every strict decoder then rejects the whole file. The other
three (brain_context excerpts x2, brain_query excerpts) feed MCP
responses, where encoding/json silently substitutes U+FFFD — so those had
been quietly eating the last character of truncated excerpts, with no
error anywhere and nothing to notice.
textutil.Truncate counts runes and appends the marker only when content
was actually dropped; an ellipsis on complete text is a lie about the
content. The test is a property, not an example: it walks the limit
across every offset of a multi-byte string and asserts utf8.Valid at each
one, so a future off-by-one cannot pass by picking a lucky boundary.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BeAp5LTscnz2W7Ubt4eJ6m
brain_pending existed the whole time four real items sat unreviewed from
2026-04-23 to 2026-07-15. The tool was never the gap — nothing ever
prompted anyone to call it. The system should be what remembers the queue
exists.
Option 2 from the issue: ride along with brain_context, which sessions
already call, so noticing an aging note costs nobody a decision to go
looking. No scheduled job, no ntfy wiring, nothing new to keep running.
Threshold-gated at 14 days, and silent below it — a notice on every
context call is one people learn to skip, which reproduces the original
failure with extra steps. It reports the whole queue once it speaks: the
threshold decides whether to talk, not what to count.
It never promotes, rejects or reorders. Age is a reason to ask a human,
not a verdict; an old note may be exactly right to promote once someone
looks. A test asserts the queue is untouched and that the payload carries
a hint rather than an action.
An unreadable raw/ dir degrades to silence — brain_context is a hot path
and must not fail because the review queue is broken.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01BeAp5LTscnz2W7Ubt4eJ6m
Returns top-N relevant brain entries for a project context. Combines
BM25 hits on project name with 2-hop graph expansion via Track A's
graphstore (when BRAIN_GRAPH_ENABLED). Closes hyperguild#28.
Notes on implementation choices that deviate slightly from the spec:
- Excerpt length: 200 chars per spec (vs the 300 used by search.Result).
truncateExcerpt clamps the already-stripped BM25 excerpt; graph-only
neighbours load their excerpt from disk via a private readExcerpt
helper (search.hydrate is unexported).
- Graph scoring: 0.6 / max(1, distance) per neighbour, so distance-1
contributes 0.6 and distance-2 contributes 0.3. BM25 hits decay
linearly from 3.0 (rank-0) to 1.0 (rank-2), giving BM25 hits a
natural ceiling above pure-graph hits while still letting a doc
surfaced via both edge types outrank a BM25-only one.
- Test placement: package mcp (internal) rather than mcp_test, because
graphReader is unexported and WithGraph only accepts *PGStore; an
internal test can install a dual-interface fake directly on s.graph
without spinning up postgres.
Bump-Type: minor
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>