docs/ befuellt - Stack-Hintergrund fuer vier Themen, Pflegeklausel in AGENTS.md ergaenzt (4.3.1, #45)

Files changed:
- AGENTS.md
- CHANGES.md
- VERSION
- docs/ownership-and-templates.md
- docs/pipeline-rationale.md
- docs/version-model.md
- docs/why-gates-are-code.md

AGENTS.md

@@ -82,6 +82,7 @@ What a file is called says who it is for and how it is loaded. This is a rule, n
 | `instructions/<name>.md` | Agents | By link, or on explicit request |
 | `instructions/<name>/SKILL.md` | Agents | By the harness, once published |
 | `types/<name>.md` | Agents + validator | Via `tools/wikitool types describe`. Split by `root:`: a page type-spec (`root: kb`) belongs to the instance and ships as `.template`; one describing a stack artifact ships verbatim |
+| `docs/<name>.md` | Agents and humans | By link, or on explicit request - never automatically, and never as instruction |
 | `INDEX.md` | Both | Generated - never hand-edited |
 
 A stage may carry both a `README.md` and a `CONTRACT.md`: different readers, different
@@ -89,6 +90,16 @@ documents. What it may not carry is the same content twice - a README that resta
 contract is a second copy that drifts. `docs verify` enforces the specific case that already
 happened once: no README may hold a copy of the `wikitool` command table.
 
+**`docs/` carries no normative sentence.** It holds why the stack is built the way it is -
+background a session consults in passing, not a rule it must follow. Anything that would bind
+belongs in a `CONTRACT.md` instead, which is what keeps invariant 8 intact here: `docs/` is
+never a second place a rule could live, only prose about rules that live elsewhere. That is also
+why nothing verifies its content - there is no rule in it to check. It has no frontmatter, no type, no index, no lint, no decay, no provenance, and no
+`COLLECTION.md` - which [kb/CONTRACT.md § Collections](kb/CONTRACT.md#collections) forbids
+outside `kb/` anyway, but the point holds independently: `docs/` stays a plain directory of
+prose, invisible to everything `tools/wikitool` does except `dist export`, which copies it
+verbatim. A fresh instance needs the reasoning as much as this one does.
+
 ## Personalization
 
 `USER.md` and `SOUL.md` are read at session start, if the runtime has not already injected
@@ -145,7 +156,8 @@ input       schema + compiler     output   derived (gitignored)
                   work/   tracked scratch, deleted when the run closes
 ```
 
-Alongside it, not part of it: `instructions/` (what agents are told to do) and this file.
+Alongside it, not part of it: `instructions/` (what agents are told to do), `docs/` (why the
+stack is built the way it is - see [File naming](#file-naming)), and this file.
 
 **By stage** - read the contract for the stage you are writing in:
 
@@ -263,3 +275,10 @@ and `tools/README.md` are part of the change that introduced a stage, a command
 not follow-up work: nobody comes back for them, and a document that describes a repo which no
 longer exists is worse than none. The mechanical half - command tables, contracts, ignore
 canaries - is checked by `tools/wikitool docs verify`; the prose half is yours.
+
+`docs/` pages are held to a different clock than those three. A README goes stale on every new
+flag; a `docs/` page goes stale only when the reasoning it wrote down stops holding - a gate
+that stops living in code, an ownership line that moves, a boundary redrawn - which is rarer
+and not tied to any one commit. Nothing checks this by construction: a page there carries no
+normative sentence (see [File naming](#file-naming)), so there is no rule for `docs verify` to
+check, only a rationale for a session to notice has gone stale and to update or retire.

CHANGES.md

@@ -20,6 +20,218 @@ their date-only headings.
 
 ---
 
+## 4.3.1 - 2026-09-03 - docs/ befuellt - Stack-Hintergrund fuer vier Themen, Pflegeklausel in AGENTS.md ergaenzt
+
+**Author:** Torben Nehmer
+
+Gitea #45: die von #38 angelegte, bis dahin leere `docs/` bekommt ihre ersten vier Seiten - frisch
+geschrieben, nicht durch Umzug aus `kb/` befuellt, jede ohne normativen Satz und mit Verweis auf
+das bindende Dokument statt einer Wiederholung seiner Regeln:
+
+- `docs/pipeline-rationale.md` - warum `raw -> types/tools -> kb -> reports` vier getrennte Stufen
+  sind und was "never re-derive, always compile" praktisch bedeutet
+- `docs/why-gates-are-code.md` - warum Mass-Update-, Publish-Remote- und Iteration-Budget-Gate in
+  `tools/wikitool` statt in einer Instruktion stehen
+- `docs/ownership-and-templates.md` - der Unterschied zwischen stack-eigenen, verbatim
+  ausgelieferten Dateien und instanz-eigenen `.template`-Dateien
+- `docs/version-model.md` - warum Drop-in-Kompatibilitaet und Migrationsbedarf zwei unabhaengige
+  Fragen sind, illustriert an der 2.0.0-Fallstudie
+
+**AGENTS.md § Changelog:** neue Klausel zur Pflege von `docs/`, ergaenzt neben der bestehenden
+Regel zu `README.md`/`EVALS.md`/`tools/README.md`. Eine `docs/`-Seite veraltet nicht wie ein
+README bei jedem neuen Flag, sondern nur, wenn die aufgeschriebene Begruendung selbst nicht mehr
+traegt - per Konstruktion ungeprueft, da die Seite keinen normativen Satz enthaelt, den
+`docs verify` pruefen koennte.
+
+---
+
+## 4.3.0 - 2026-09-03 - docs/ als ausgelieferter Hintergrund-Ort; Decision-Seiten bleiben in kb/, Decay-Skip fuer concept_type: decision
+
+**Author:** Torben Nehmer
+
+Gitea #38: `dist export` lieferte bislang keine einzige `kb/`-Seite aus - eine frische Instanz
+bekam den Stack, aber keinen Grund für seine Form. Die dokumentierte `adr-NNN-`-Konvention in
+`kb/concepts/COLLECTION.md` existierte zudem nur auf Papier: keine der sieben
+`concept_type: decision`-Seiten folgte ihr, und `confidence_decay()` lief bedingungslos über sie
+- ein Kategorienfehler, weil Zeitablauf eine Entscheidung nicht falscher macht, nur Supersession
+tut das.
+
+**Neu:** `docs/` - ein inertes Verzeichnis für Stack-Hintergrund (warum der Stack so gebaut ist,
+nicht was diese Instanz entschieden hat). Keine Frontmatter, kein Typ, kein Index, kein Lint,
+keine Decay, keine Provenance, keine `COLLECTION.md`. `dist export` liefert es verbatim aus, wie
+`instructions/` und `types/`. Befüllung folgt in Gitea #45.
+
+**Verworfen, nach Prüfung:** ein Umzug der sieben Decision-Seiten nach `decisions/`. Der
+Subtyp-Floor aus #28 verlangt mindestens eine Seite je deklariertem `concept_type`, und ein
+Umzug hätte `decision` auf null gebracht; dazu zeigen 89 Wikilinks aus `kb/` sowie
+tool-eigene Frontmatter-Arrays auf die sieben, und `links.py`/`xref add` kennen kein Ziel
+außerhalb `kb/`. Die sieben bleiben in `kb/concepts/`, ebenso ein zweiter, separat erwogener
+Rename (`docs verify` → `parity verify`) - der wäre nur nötig gewesen, wenn ein Befehl auf das
+Verzeichnis `docs/` wirkt, und keiner tut das.
+
+**Geändert:**
+- `confidence_decay()` überspringt `concept_type: decision` strukturell (kategorische Ausnahme,
+  nicht als Brücke gebaut - Begründung im Docstring).
+- `kb/concepts/COLLECTION.md` § Decisions ersetzt die tote ADR-Vorlage durch die real gelebte
+  Form: eine Entscheidung ist eine gewöhnliche Concept-Seite, organische Prosa, kein
+  `adr-NNN-`-Präfix, `**Status:**` optional, Supersession per `supersedes`-Link.
+- `kb/CONVENTIONS.md` § Naming und `instructions/kb-profiles.md` (Profil `german`) korrigiert -
+  beide dokumentierten noch die verworfene `adr-NNN-`-Namensregel.
+- `AGENTS.md` § File naming und § Routing: `docs/`-Zeile, plus die Regel, dass `docs/` keinen
+  normativen Satz trägt (das hält Invariante 8 heil - was binden würde, gehört in einen
+  Contract).
+- `tools/CONTRACT.md`: Klarstellung, dass `docs verify` Dokumentations-Parität prüft, nicht das
+  `docs/`-Verzeichnis, sowie `docs/` in der `dist export`-Zeile ergänzt.
+
+Additiv und in beide Richtungen drop-in: eine bestehende Instanz ohne `docs/` exportiert
+weiterhin identisch (leerer `_copy_tree`-Treffer), eine Instanz mit `docs/` bekommt es ab jetzt
+mitgeliefert. Kein Feld, kein Kommando ändert sein Verhalten für bestehenden Inhalt.
+
+**Migration:** none required.
+
+Berührt: `tools/chemenu/commands/confidence_decay.py`, `tools/chemenu/commands/dist_cmd.py`,
+`tools/chemenu/tests/test_confidence_decay.py`, `tools/chemenu/tests/test_dist_cmd.py`,
+`kb/concepts/COLLECTION.md`, `kb/CONVENTIONS.md`, `instructions/kb-profiles.md`, `AGENTS.md`,
+`tools/CONTRACT.md`.
+
+---
+
+## 4.2.0 - 2026-09-03 - Korpus-Kuratierungsrichtlinie: Untergrenzen und Leitplanke für reaktive Fixes
+
+**Author:** Torben Nehmer
+
+Ein Demo-Korpus will klein und stabil sein, ein Testbett groß, unordentlich und in Bewegung -
+dieses Repo verlangt seit der Veröffentlichung beides vom selben `kb/` (Gitea #28). Die Sitzung
+vom 2026-09-02 hatte Fixture, `--with-demo` und ein zweites Repo bereits verworfen; offen blieb
+nur, wie kuratiert "kuratiert genug" heißt und welche Leitplanke reaktive Fixes bekommen.
+
+**Neu:** `instructions/dev/corpus-policy.md`. Fünf Untergrenzen, jede mit einer bestehenden
+`wikitool`-Prüfung messbar, keine davon durch neuen Tool-Code: jeder Seitentyp und jeder
+deklarierte Subtyp mit mindestens einer Seite, mindestens fünf Seiten mit mindestens drei
+Quellen, ein bis zehn Orphan-Seiten, im Schnitt mindestens vier ausgehende Wikilinks pro Seite.
+Gemessen am 2026-09-03: 181 Seiten, alle Typ-/Subtyp-Floors erfüllt, 12 Seiten mit ≥3 Quellen, 3
+Orphans, Ø 6,2 ausgehende Links - der Korpus war bereits groß genug, ohne dass eine einzige
+Seite eigens dafür angelegt werden musste. Eine Untergrenze wird nie durch eine erfundene Seite
+gefüllt, sondern durch eine echte Quelle beim nächsten passenden Ingest - Invariante 3 gilt
+unverändert.
+
+**Die Leitplanke für reaktive Fixes** unterscheidet drei Stufen: punktuelle Änderungen (immer
+erlaubt, gewöhnliche Arbeit), korpusweite Änderungen (nur geplant, mit eigenem Issue und
+`work/`-Run - trifft eine Session das Mass-Update-Gate während sie etwas anderes tat, holt sie
+sich nicht den `--confirm`-Token, sondern stoppt und legt ein Issue an) und reaktive Eingriffe
+in Korpusinhalt, um einen Test grün zu machen oder einen Tool-Bug zu umgehen (nie erlaubt,
+Invariante 7). Das Verhältnis zu `kb_dir`/`raw_dir` und `test_pipeline_l0.py` bleibt wie im
+ursprünglichen Befund: kleiner, isolierter Fall in der Fixture, großer, vernetzter Fall in
+`kb/` - keine Fixture-Extraktion aus dem Korpus.
+
+Dev-only und rein additiv - kein Feld, kein Kommando, keine Datei außerhalb von
+`instructions/dev/` ändert sich, daher `--minor` ohne `--breaking`.
+
+**Migration:** none required.
+
+Berührt: `instructions/dev/corpus-policy.md` (neu),
+`instructions/dev/stack-dev/SKILL.md` (Schritt 2, Routing-Zeile).
+
+---
+
+## 4.1.2 - 2026-09-03 - Issue-Abschluss ist ein Body-Rewrite, nicht nur ein Kommentar
+
+**Author:** Torben Nehmer
+
+Aufgefallen beim Schließen von #44: der Abschlussbericht stand als Kommentar da, der Body
+darunter weiterhin als offene Arbeit — Abschnitt „Zu entscheiden" über eine längst getroffene
+Entscheidung, ungehakte Checkliste, Präsens über einen Defekt, den es nicht mehr gab.
+
+Die Regel gab es dafür schon: Schritt 2 von `instructions/dev/issue-tracking.md` sagt, der Body
+ist die aktuelle Wahrheit und wird umgeschrieben, wenn sich der Stand ändert. Nur ließ die
+Formulierung offen, *wann* — und Schritt 7 („Close with what actually happened") war vollständig
+erfüllbar, ohne den Body anzufassen. Ein Abschlussbericht im Kommentar fühlt sich beim Schreiben
+vollständig an; dass der Body dabei zurückbleibt, merkt erst der nächste Leser.
+
+**Schritt 2 ist deshalb schärfer geworden: der Body ist das Plan-File dieses Stacks.** Dasselbe,
+was das Plan-Dokument eines Harness ist, und genauso gepflegt — fortlaufend, sobald etwas darin
+nicht mehr stimmt, nicht am Ende. Der Maßstab ist der Abbruch, nicht der Meilenstein: eine
+Session kann jederzeit enden, und was der Body in diesem Moment sagt, ist die vollständige
+Übergabe. Eine frische Session muss zu **jedem** Zeitpunkt allein aus dem Body weiterarbeiten
+können, ohne Kommentare rückwärts zu lesen und ohne einen Menschen, der es neu erklärt. Entschieden
+ersetzt die Frage, erledigt hakt das Kriterium ab, verworfen steht mit Begründung dort, wo das
+Kriterium stand.
+
+Schritt 7 ist damit kein Sonderakt mehr, sondern die letzte dieser Aktualisierungen: erst Body
+auf den Endstand, dann schließen, dann die Changelog-Zeile aus Schritt 3. Wer Schritt 2 befolgt
+hat, ist fast fertig; wer nicht, zahlt die ganze Schuld im schlechtesten Moment — der
+geschlossene Body ist die Fassung, die danach alle lesen und niemand mehr aufsucht. #44 steht
+als Beispiel drin.
+
+Schritt 3 zieht die Konsequenz: **ein Kommentar pro Session-Umfang, nicht pro Edit.** Ein
+fortlaufend gepflegter Body mit einem Changelog-Kommentar je Änderung wäre Lärm; triviale Pflege
+braucht gar keinen. Der `stack-dev`-Skill sagt es beim Aufgreifen mit, weil dort die Entscheidung
+fällt, ob eine Session den Body überhaupt anfasst.
+
+**Und die ehrliche Antwort auf die Frage nach dem Tooling: es gibt keins, und es soll keins
+geben.** `wikitool` kennt diesen Tracker nicht. Es wird an Instanzen ausgeliefert, die unter
+dieser URL keine Issues haben, während `instructions/dev/` von `dist export` gepruned wird —
+ein Gitea-Client im ausgelieferten Tool wäre eine Dev-Abhängigkeit, die jede Instanz mitträgt,
+um ein Board zu prüfen, das keine von ihnen hat. Der Tracker ist ausschließlich über
+`gitea-mcp` erreichbar, also in einer Session, durch einen Agenten.
+
+Kein `docs verify` fängt also einen geschlossenen Issue, dessen Body offen klingt, einen Body,
+der seinen eigenen Kommentaren widerspricht, oder ein fehlendes Pflichtlabel. Das steht jetzt
+als eigener Abschnitt „What no tool checks" in der Instruktion — nicht als Bedauern, sondern als
+Begründung dafür, warum die Reihenfolge in Schritt 7 ausgeschrieben ist statt aus Schritt 2
+erschlossen zu werden.
+
+---
+
+## 4.1.1 - 2026-09-03 - Testisolation: kb_dir repointet config.ROOT, lint löst Kollektionen gegen den übergebenen Baum auf
+
+**Author:** Torben Nehmer
+
+Issue #44, gefunden beim Bau der Migrations-Gate-Tests für 4.1.0: die `kb_dir`-Fixture baute
+ihren Baum unter `tmp_path`, ließ `config.ROOT` aber auf dem echten Checkout stehen. Jeder
+Codepfad, der eine Datei über `config.ROOT`/`config.KB_DIR` auflöst statt über das übergebene
+Verzeichnis, traf damit das echte Repository.
+
+**Der laute Fall** war ein Test, der `kb_state.write_kb_state()` rief und dabei das
+`.wikitool-kb.json` des Repos überschrieb — Applied-Ledger leer statt zwei Einträgen. In
+`git status` sofort sichtbar und reversibel; bei einer gitignorierten Datei wäre es das nicht
+gewesen.
+
+**Der stillere Fall** ist der teurere. `lint`s Kollektions-Lookup löste eine Seite gegen
+`config.KB_DIR` auf. Für eine Seite unter `tmp_path/kb/` warf das `ValueError`, die Funktion
+antwortete „keine Kollektion", und die Label-Autorisierung übersprang die Kante wortlos.
+`unauthorised_labels` war damit faktisch ungetestet — jeder Test, der das Finding hätte
+auslösen können, bekam eine leere Liste und behauptete nichts. Ein grüner Lauf, der wie eine
+Zusicherung aussah.
+
+**Der Fix ist der Codepfad, nicht die Fixture.** `run_lint()` bekommt ein Verzeichnis
+übergeben und löst jetzt auch intern dagegen auf; `authorised_labels()` bekommt denselben Baum
+gereicht, statt auf `config.KB_DIR` zurückzufallen. Der Regressionstest lintet einen Baum, von
+dem `ROOT` bewusst wegzeigt — genau der Fall, den die alte Auflösung verschluckte. Eine Funktion,
+die ein Verzeichnis entgegennimmt, löst dagegen auf: keine Fixture kann diese Form von außen
+reparieren.
+
+**Beide Korpus-Fixturen repointen jetzt.** `kb_dir` tut, was `raw_dir` längst tat — `ROOT` auf
+das eigene `tmp_path`, plus `use_shipped_type_specs()`. Der Suite-Lauf kippte dadurch keinen
+einzigen Test. Die lokale `rooted_kb`-Umgehung aus 4.1.0 entfällt damit; die Auswahl zwischen
+zwei fast gleichen Fixturen war Wissen, das nirgends stand.
+
+**Und ein Wächter für die ganze Klasse.** `repository_tree_guard` (session-scoped, autouse)
+vergleicht `git status --porcelain` vor und nach dem Lauf und lässt die Suite scheitern, wenn
+sich im Checkout etwas bewegt hat — zwei `git status`-Aufrufe pro Lauf, deshalb per Default an.
+Er vergleicht vorher gegen nachher statt einen sauberen Baum zu verlangen, sagt also nichts über
+die unveröffentlichte Arbeit des Entwicklers. Den Verursacher benennt er nicht;
+`CHEMENU_TREE_GUARD=each` prüft nach jedem Test und tut es. Ohne git oder außerhalb eines
+Repositorys sind beide still.
+
+Was der Wächter nicht sieht: eine Prüfung, die unter Test nichts tut, schreibt keine Datei.
+Dagegen hilft nur ein Test, der das Finding tatsächlich auslöst — der neue tut das.
+
+`instructions/dev/testing-conventions.md` hat dafür einen eigenen Abschnitt („Which tree a test
+writes into"), einen Schritt in der Checkliste und die Regel für neue Fixturen.
+
+---
+
 ## 4.1.0 - 2026-09-03 - Link-Taxonomie: Lint-Findings hart ab kb_version 4.0.0, outbound: an das Type-Spec gebunden, part-of/composition als Inversenpaar
 
 **Author:** Torben Nehmer

VERSION

@@ -1 +1 @@
-4.1.0
+4.3.1

docs/ownership-and-templates.md

@@ -0,0 +1,71 @@
+# Ownership and Templates
+
+Chemenu ships two kinds of files side by side, and at a glance they look the same: both are
+plain markdown, both sit in the repo root or under `kb/`, both get read at session start. But a
+stack upgrade treats them completely differently. Some - [AGENTS.md](../AGENTS.md),
+[kb/CONTRACT.md](../kb/CONTRACT.md), the per-stage contracts - are identical in every instance
+that runs this stack and can simply be overwritten by the next release. Others - `USER.md`,
+`SOUL.md`, `kb/CONVENTIONS.md`, `ENVIRONMENT.md` - describe one particular instance, and
+overwriting them would silently erase a choice someone made on purpose.
+
+## Two different kinds of truth
+
+The stack-owned files describe how the tool works. `kb/CONTRACT.md` opens by saying it holds
+what `tools/wikitool` enforces or what follows mechanically from how it operates - see
+[kb/CONTRACT.md](../kb/CONTRACT.md), lines 10-13. That kind of statement doesn't vary by
+instance: the compiler behaves the same way regardless of who is running it, so the sentence
+describing that behavior can be copied byte-for-byte into every checkout without becoming
+wrong anywhere.
+
+The instance-owned files describe a choice: which language pages are written in, what tone the
+agent takes, who the operator is, which git remote is authoritative, which MCP servers are
+reachable. None of that follows from the tool's mechanics - two instances of the identical
+stack can answer all of these differently and both be correct. [AGENTS.md § Personalization](../AGENTS.md#personalization)
+frames the split the same way for `kb/CONTRACT.md` versus `kb/CONVENTIONS.md`: "the split is by
+who may change the sentence, not by what it is about." A rule about page structure could in
+principle have been written per-instance too, but then every instance answering "not German" to
+setup would be hand-editing a file the stack also ships, and the next `dist export` merge would
+hand the instance's own file back to it, discarding the customization.
+
+## Why silent overwrite is the failure being designed against
+
+A stack update is meant to be a routine, low-risk operation: pull the latest release, get
+whatever fixes and features shipped since the last one. That only stays low-risk if the update
+knows which files it's allowed to touch. If `USER.md` or `kb/CONVENTIONS.md` were treated the
+same as `AGENTS.md` - shipped and periodically re-copied - an upgrade would quietly replace a
+description of *this* operator, in *this* language, with whatever placeholder or default the
+stack maintainers wrote. The damage wouldn't be loud: nothing crashes, the files still parse,
+the agent just starts acting on the wrong premises until someone notices the voice or the
+language changed.
+
+Keeping the boundary at the file level, rather than trying to merge changes within a shared
+file, means an upgrade never has to guess which lines are "stack" and which are "instance" -
+the file itself already answers that.
+
+## Why a `.template`, not just an absent file
+
+The mechanism for instance-owned content is a `.template` file the distribution ships instead
+of the real one - `USER.md.template`, `SOUL.md.template`, `kb/CONVENTIONS.md.template`,
+`ENVIRONMENT.md.template`. An alternative would have been to ship nothing at all and let a
+brand-new instance start from a blank page. The template exists because a blank page doesn't
+tell [instructions/setup-instance.md](../instructions/setup-instance.md) what shape the answer
+should take, and it gives nothing for a validator to check afterward.
+
+A template carries a placeholder value - a sentinel - in the fields that need a real answer.
+Setup interviews the operator and replaces the sentinel with what they actually said. That
+gives `doctor` a mechanical way to tell "personalized" from "not yet": a file that still
+contains the sentinel hasn't been through setup, regardless of whether the file exists. That's
+also why `ENVIRONMENT.md` only warrants a WARN rather than a FAIL when absent - see
+[AGENTS.md § Environment](../AGENTS.md#environment) - while a missing or unfilled
+`USER.md`/`SOUL.md`/`kb/CONVENTIONS.md` is a harder failure: `ENVIRONMENT.md` describes one
+checkout among possibly several and is gitignored for that reason, so its absence is a normal
+state rather than a sign setup was skipped.
+
+## The consequence in practice
+
+Running a stack upgrade against an existing instance boils down to: overwrite the verbatim
+files, leave the `.template`-sourced files alone. The verbatim files are safe to replace
+wholesale because they were never instance-specific to begin with - identical content going
+back in changes nothing an instance actually decided. The template-sourced files were filled in
+once, by a person, for a reason, and nothing about a newer release of the stack's mechanics
+gives it standing to override that.

docs/pipeline-rationale.md

@@ -0,0 +1,64 @@
+# Why the pipeline has four stages
+
+Chemenu could, in principle, be one directory: drop a file in, ask a question, get an answer
+computed fresh each time. It isn't built that way. The pipeline in
+[AGENTS.md](../AGENTS.md#routing) - `raw/` -> `[types/ + tools/]` -> `kb/` -> `reports/`, with
+`work/` alongside rather than inside it - separates *material* from *meaning* from
+*byproduct*, and each seam exists because collapsing it costs something specific.
+
+## Why raw material stays untouched
+
+[raw/CONTRACT.md](../raw/CONTRACT.md) keeps a source exactly as it arrived. The reasoning is
+simple once stated: the moment someone "cleans up" or reformats a source on the way in, the
+thing later claims get checked against is no longer the thing that was actually said. An
+immutable `raw/` means a citation always resolves to the original, not to somebody's tidied
+memory of it. It also draws a trust boundary in one place instead of scattering it - everything
+past `raw/` can be treated as reviewed, because nothing upstream of it silently already was.
+
+## Why extraction happens once, through a schema
+
+[types/type-spec.md](../types/type-spec.md) is what stands between a raw file and a `kb/` page:
+a type-spec defines what a conforming instance of a page looks like, and the compiler
+(`tools/wikitool`) applies it. The alternative - every query re-reading and re-interpreting the
+source on demand - would mean paying the cost of understanding the material every single time,
+and getting a slightly different answer each time depending on how the question was phrased.
+Extracting once, against a fixed schema, turns "re-read and re-guess" into "look up what was
+already compiled." That is the "never re-derive, always compile" principle from
+[AGENTS.md](../AGENTS.md): understanding a source is expensive and worth doing exactly once,
+after which it becomes a cheap, stable lookup.
+
+## Why a `kb/` page has to stand on its own
+
+[kb/CONTRACT.md](../kb/CONTRACT.md) sets the bar for the compiled layer: a page should answer a
+future question without sending the reader back to the source it came from. That's the payoff
+of compiling in the first place - if every answer still bottomed out in "go re-read the raw
+file," the `kb/` layer would just be a pointer with extra steps, and the cost of extraction
+would have bought nothing. A page that stands alone is what makes the corpus fast and
+consistent to query: the work of understanding is already sitting there, done.
+
+## Why `reports/` doesn't need to be maintained
+
+[reports/CONTRACT.md](../reports/CONTRACT.md) treats most of what lands in `reports/` -
+lint output, telemetry traces - as disposable. The structural content of a lint report can be
+recomputed from the tree at any commit, so keeping an old copy around would just be a second
+version of something the tool can already answer on demand, and a second copy is exactly the
+kind of thing that quietly goes stale. Treating it as derived output rather than a fourth thing
+to maintain means there is nothing there to fall out of sync - regenerating it is cheaper than
+reconciling it. The one part that genuinely can't be recomputed - the judgment a pass produced -
+is carried out into `kb/` or `kb/log.md` before the report itself is discarded, which is the
+distinction between what's recomputable and what isn't.
+
+## Where `work/` fits
+
+[work/CONTRACT.md](../work/CONTRACT.md) describes a workshop, not a fifth pipeline stage: a
+place for the notes, extracts and open decisions of a task that spans more than one session, on
+its way toward becoming a `kb/` page. It sits beside the raw -> kb -> reports flow rather than
+inside it - closer in spirit to a desk than to a conveyor belt.
+
+## The shape this produces
+
+Four stages, each answering a different question: `raw/` - what was actually said; `types/` +
+`tools/` - how to turn that into structured understanding; `kb/` - what is now known;
+`reports/` - what a pass over the corpus noticed in passing. Keeping them separate is what lets
+each one be trusted for what it is, instead of every layer having to double as all four at
+once.

docs/version-model.md

@@ -0,0 +1,84 @@
+# Why the stack version splits compatibility from migration
+
+A stack version number looks like it answers one question. It actually answers two, and the two
+are independent of each other.
+
+## Two questions, not one
+
+The first question is whether the new version is a drop-in replacement for the old one - whether
+an existing instance can install it, and can also go back, without anyone doing hand-work. That
+is what a version number *is*: a promise. The second question is whether the existing corpus in
+`kb/` needs to change shape to keep working under the new version. These sound like the same
+question, because most of the time a change that breaks compatibility also happens to touch
+content, and most of the time a change that leaves content untouched also happens to be
+compatible. The correlation is real; it just is not a law. `instructions/dev/version-parts.md`
+carries the actual test for telling them apart and the steps that follow from it - this page is
+about why the split exists at all.
+
+## Why "kb/ untouched" is not proof of anything
+
+The tempting shortcut is: if no page in `kb/` had to change, the bump can't be that serious. This
+is exactly backwards for a class of changes that live entirely outside the corpus - a renamed
+release artefact, a Python import path, an environment variable, the URL an instance's own
+updater points at. None of those touch a single page. All of them can strand an existing
+instance just as thoroughly as a rewritten type-spec would. The corpus is the part of the stack
+that looks at itself; the compatibility question is about everything an instance depends on to
+keep functioning, most of which the corpus never sees.
+
+## Reading compatibility off the leftmost non-zero component
+
+Semantic versioning gives every component a job, but only one of them is where an existing
+instance's tooling actually looks to decide "is this safe." On a `2.x` stack that is MAJOR; on a
+still-pre-1.0 `0.x` stack, by the same convention, it's MINOR - the leftmost slot that isn't
+pinned to zero is the one an automated updater treats as the compatibility boundary. Bump
+anything to its left, or bump that slot itself, and the promise changes. Everything to the right
+of it can move as freely as the project likes without touching that promise. This is why the
+question "is it boundary-crossing" always resolves to one specific digit, not to a feeling about
+how big the change is.
+
+## Downgrade is half the promise
+
+It's natural to test compatibility by only asking "does the upgrade work." The other half -
+"can an instance that upgraded put the old version back and land where it started" - carries
+equal weight, and it's the half that's easy to forget because forward motion is what everyone is
+testing for anyway. A state file the old version can no longer parse, a generated index in a new
+shape, a stamp file that got renamed: none of these have to break the upgrade to break the
+downgrade. An instance that can go forward but not back has already lost the property a
+compatible version number is supposed to guarantee.
+
+## A promise made to a machine, not only to a person
+
+A human reading a changelog can absorb "this technically isn't compatible but it's fine, just
+update those two things by hand." An instance's own update mechanism cannot. It reads a version
+number, decides whether to pull the new release, and has no channel for nuance - which is exactly
+why the update path itself is one of the sharpest ways to cross the boundary invisibly: if the
+new version moves where updates come from, the very channel that would have told an instance to
+adjust is the channel that just broke. The version number isn't documentation aimed at a reader;
+it's an input consumed by code that has no other way to ask.
+
+## The 2.0.0 story
+
+This isn't hypothetical for this stack. The rebranding that produced Chemenu renamed the repo,
+the release artefact, and the Python package - and left every page in `kb/` untouched. The first
+instinct was a MINOR bump, on the reasoning that nothing in the corpus needed migrating. That
+reasoning was correct on its own terms and answered the wrong question. Three things broke
+underneath it: every existing instance's `update_url` pointed at a repo path that no longer
+existed and, because it's a machine-written file, couldn't be hand-repaired; the release artefact
+name changed, breaking every download script and pin against it; and the import name changed,
+breaking anything importing the package from outside the shipped tree. The corpus had nothing to
+say about any of this, because none of it lived in the corpus.
+
+What caught the mistake was a person looking at the diff and asking whether it really was a
+drop-in replacement, not a validator. No check in `docs verify` or anywhere else confirms that a
+version part was chosen correctly - it only confirms that a boundary-crossing bump documents
+what it breaks. The 2.0.0 entry in `CHANGES.md` carries the corrected reasoning in full, and the
+version bump that shipped it was `--major --no-migration`: boundary-crossing and untouched
+corpus, at the same time, which is precisely the combination the two-question split exists to
+make visible.
+
+## Where the procedure lives
+
+The drop-in test, the catalogue of changes that cross the boundary with no page touched, and the
+steps for a boundary-crossing bump - the `--breaking` line, the migration document or
+`--no-migration` reason, talking to the user before bumping - are one procedure, kept at one
+place: [instructions/dev/version-parts.md](../instructions/dev/version-parts.md).

docs/why-gates-are-code.md

@@ -0,0 +1,57 @@
+# Why gates are code
+
+Chemenu has three hard limits - the Mass-Update Gate, the Publish-Remote Gate, and the
+Iteration Budget Gate - and all three live inside `tools/wikitool`, not in a paragraph of
+instructions an agent reads and follows. The rules themselves, and what to do when one trips,
+are in [AGENTS.md § Gates](../AGENTS.md#gates) and [instructions/gates.md](../instructions/gates.md).
+This page is only about the design choice underneath them: why code, and why these three
+mechanisms in particular.
+
+## A suggestion an agent can talk itself past
+
+An instruction like "don't publish too much at once" or "don't loop forever" lives in the same
+place as every other piece of guidance a session is holding - alongside the task, the user's
+last message, and whatever context made the moment feel urgent. Under pressure, or with a
+plausible-sounding reason ("this batch is different, it's mechanical"), that guidance can be
+reasoned around without anyone deciding to break a rule. Nothing enforces it; it just competes
+for attention with everything else in the context window, and sometimes loses.
+
+A check compiled into the tool doesn't have that problem, because it isn't part of the
+conversation at all. It runs before the command dispatches, regardless of how convincing the
+case for skipping it seemed a moment earlier. The difference isn't that code is smarter than a
+well-written instruction - it's that code doesn't get talked into anything.
+
+## Why three different mechanisms, not one
+
+The three gates ask three different questions, and each one's shape follows from what kind of
+question it is.
+
+The Mass-Update Gate asks *is this change too large to publish unreviewed* - a judgment that
+varies changeset by changeset, so it clears with a `--confirm` token tied to the specific
+output the user just read. Approval is scoped to that one publish.
+
+The Publish-Remote Gate asks something underneath that: *is this even the right repository*.
+That's not a per-push judgment, it's a standing property of the checkout - true or false for
+every publish that checkout will ever attempt, not just this one. A confirm token would let an
+agent clear it once and then treat the answer as settled, which is exactly backwards for a
+question whose answer shouldn't move at all mid-session. The only way past it is the user
+editing `.wikitool-remotes.json` directly, outside the gate's own flow.
+
+The Iteration Budget Gate asks a third kind of question - not "is this instance correct" but
+"has this session stopped making progress." That's read from the shape of the call history
+itself (call count, repeated identical calls), not from anything about the content of any one
+call.
+
+## Numbers that come from measurement, not intuition
+
+The iteration ceiling didn't start where it sits now. It used to run 15-25, borrowed from a
+general rule of thumb, until four real ingest runs measured 24, 26, 29 and 30 calls apiece -
+every one of them an ordinary workflow doing nothing wrong, and every one of them at or past
+where the old ceiling would have refused it. A limit that the normal case keeps tripping stops
+functioning as a limit; it becomes background noise a session learns to route `--override-budget`
+around as a matter of course, and the whole point of a hard-coded check is that it isn't supposed
+to feel routine.
+
+That's the deeper reason these numbers live in a tool rather than in prose: prose is read once
+and remembered loosely, but a threshold enforced every call is tested by every call, and a
+threshold that fails its own test gets noticed and re-measured rather than quietly ignored.

instructions/dev/corpus-policy.md

@@ -0,0 +1,94 @@
+---
+type: types/instruction.md
+name: corpus-policy
+description: What "curated enough" means for kb/ when it is demo and testbed at once, the measurable floors that define it, and what a reactive fix to the corpus may and may not do.
+---
+# Keep kb/ curated enough to develop against, without a second corpus
+
+This instance runs one `kb/` for two purposes at once: a public demo and the testbed this stack
+is developed against. There is deliberately no fixture corpus, no `--with-demo` export, and no
+second repository - see Gitea #28. The corpus's size and shape are set by what targeted
+development needs, not by a synthetic fixture size or a demo aesthetic.
+
+## When to run
+
+- Before judging whether the corpus can exercise a change under development - ranking, index
+  scaling, orphan detection, a new label, a new type-spec.
+- Before a reactive fix touches `kb/` content rather than the failing code - the floors below
+  are what decides whether the fix may proceed as-is.
+- Picking up Gitea #28 or #30, or any issue that references this file.
+
+## The floors
+
+Each is mechanically checkable with an existing `wikitool` command; none needs new tool code.
+A floor exists to keep some class of bug observable, not to describe an aesthetic target - so
+when a session is about to make one of these numbers *worse*, that is the signal to stop and
+think, not a number to defend for its own sake.
+
+| Floor | Check | Why this number |
+|---|---|---|
+| Every page type has ≥1 page | `wikitool search --field type=types/<t>.md` | A type with zero pages means its schema, its collection contract and its lint rules are unexercised |
+| Every declared subtype has ≥1 page | `wikitool search --field <x>_type=<v>` | Same reasoning, one level down - `entity_type`, `concept_type`, `source_type` |
+| ≥5 pages corpus-wide with ≥3 `sources:` entries | one-off script, see below | Provenance fan-in - multiple sources backing one claim - is a real case only a handful of pages exercise; fewer than 5 and a provenance-index bug can hide |
+| Orphan pages (no inbound link) between 1 and 10 | `wikitool lint` | Zero orphans makes orphan detection itself unobservable; more than 10 means the corpus stopped being curated |
+| Average outbound wikilinks per page ≥4 | one-off script, see below | Below this, ranking and graph-traversal work has too little structure to exercise |
+
+A floor is a lower bound only. There is no upper bound on page count or on any of these numbers
+except the orphan ceiling above - a corpus that outgrows these floors through real ingests is
+not a problem this file cares about.
+
+**Measured 2026-09-03** (see Gitea #28): 181 pages, 14/14 types and subtypes covered, 12 pages
+with ≥3 sources, 3 orphans, 6.2 average outbound links. All floors held without any manufactured
+content - the corpus was already big enough when the question was asked.
+
+A type or subtype sitting at exactly the floor - one page - shows no set-level bugs, only that
+the type is *reachable*. That is a soft target for the next `wiki-ingest` that happens to
+produce a matching page, never a reason to write one: filing an unsourced page to clear a floor
+is exactly what AGENTS.md invariant 3 forbids, floor or no floor. The same holds for an
+authorised link label with zero live uses (`wikitool xref` reports these) - fill it when a real
+edge calls for it, never manufacture one to exercise the label.
+
+To check the two floors without a dedicated command, walk `kb/**/*.md` (excluding
+`INDEX.md`/`COLLECTION.md`/`CONTRACT.md`/`CONVENTIONS.md`), parse frontmatter, and: count pages
+whose `related:` array (resolved against page titles) has ≥3 entries for outbound density; count
+`sources:` array length ≥3 for the provenance floor. `wikitool search` and `wikitool lint`
+cover everything else in the table.
+
+## What a reactive fix may do to kb/ content
+
+Three tiers, by how much of the corpus a change touches:
+
+1. **Pointwise - always allowed.** Creating, updating, renaming or deleting a single page
+   through the normal tools (`new`, `touch`, the page-lifecycle procedure), below the
+   Mass-Update Gate's threshold. This is ordinary work and needs no special permission.
+2. **Corpus-wide - planned only, never reactive.** A migration, a vocabulary sweep, a bulk
+   `touch` across many pages. This needs its own issue and, per `work/CONTRACT.md`, a `work/`
+   run - never a same-session reaction to whatever the session was originally doing. If a
+   session hits the Mass-Update Gate (exit 42, see `instructions/gates.md`) while working on
+   something else, it does not fetch the `--confirm` token to push through: it stops, opens an
+   issue for the corpus-wide change, and finishes the original task without it.
+3. **Reactive - never allowed.** Deleting or reshaping a page to make a failing test pass;
+   restructuring corpus content to route around a tool bug (AGENTS.md invariant 7); using
+   `kb/` as a scratch surface for a tool experiment. If a stack change under development needs a
+   corpus shape that does not exist, build it as a pytest fixture (see the next section) -
+   never manufacture it in `kb/`.
+
+## Relationship to the test fixtures
+
+`tools/chemenu/tests/conftest.py`'s `kb_dir`/`raw_dir` fixtures and `test_pipeline_l0.py` cover
+the **small, isolated** case: a handful of pages, built fresh per test, hermetic. `kb/` covers
+the **large, connected** case: 181+ pages, grown link density, real provenance history that no
+per-test fixture reconstructs economically. The cut: if a `tmp_path` tree can reproduce what the
+test needs, it belongs in a fixture; if the test needs density or scale that only a grown corpus
+has, it belongs against `kb/`. Neither absorbs the other's job - see
+[testing-conventions.md](testing-conventions.md).
+
+## Decision points
+
+- **A floor would be violated by an in-progress change - is that a blocker?** Only for the
+  orphan ceiling and the type/subtype floors, since those two can go to zero. The density and
+  provenance floors move gradually with ordinary ingests and are not gating on any single
+  session.
+- **Corpus is "too small" for a feature under development?** That is not this file's problem to
+  solve by adding pages - see tier 3 above. Either the feature waits for a real ingest to supply
+  the shape, or it gets a pytest fixture.

instructions/dev/issue-tracking.md

@@ -28,8 +28,12 @@ issues at that URL, which is exactly why `dist export` excludes
   an assumption nobody has checked, a decision that needs the user.
 - Picking an issue up: before doing anything else, read the body as the current
   spec, and re-label it if the ground has moved since.
+- **While working on one:** the body is updated as the state moves, not at the
+  end (step 2). A session that is interrupted leaves the body as its handover.
 - Prioritising: deciding what to pick up next, or re-labelling after the ground
   moved.
+- Closing one: the body is rewritten to its final state first, and only then
+  closed (step 7).
 
 ## Steps
 
@@ -38,23 +42,47 @@ issues at that URL, which is exactly why `dist export` excludes
    specific files or commands involved. An issue that only makes sense to
    whoever wrote it is a note, and notes were the problem.
 
-2. **Treat the body as the current truth, not as a historical first post.**
-   Work on one issue spans several sessions, often weeks apart, and the body is
-   the only thing that connects them: a session opening the issue must be able
-   to reconstruct what is decided and what is still open from the body alone,
-   without a human re-explaining it. So when the state changes, **rewrite the
-   body** - do not append to a text that has become wrong. An additively grown
-   log forces every later reader to reconstruct the current state by filtering
-   the whole history.
+2. **The body is the working state, not a historical first post - keep it
+   current as you go.** It is this stack's plan file: the same thing a harness's
+   own plan document is, and it is maintained the same way. Not written once,
+   not brought up to date at the end, but **updated whenever something in it
+   stops being true** - a decision made, a criterion met, an approach ruled out,
+   a new constraint found.
+
+   The test is an abort, not a milestone. A session can end at any moment - an
+   interrupt, a context limit, a crash, a human walking away - and whatever the
+   body says at that instant is the entire handover. So the standard is: **at
+   every point, a fresh session must be able to open the body and pick the work
+   up from there**, without a human re-explaining it and without reading back
+   through the comments. If the body would mislead someone who read it right
+   now, it is already out of date, whether or not the work is finished.
+
+   That means updating *during* the work, not only at its end:
+
+   - a decision gets made → the decision and its reasoning replace the question
+   - an acceptance criterion is done → tick it, in the same session that did it
+   - something turns out differently than the issue assumed → the assumption is
+     corrected where it stands, not contradicted three paragraphs later
+   - work is deferred or dropped → say so, with the reason, where the criterion is
+
+   **Rewrite, never append.** Do not add to a text that has become wrong: an
+   additively grown log forces every later reader to reconstruct the current
+   state by filtering the whole history, which is the exact cost the body exists
+   to remove. Comments carry the history (step 3); the body carries the state.
 
    Body rewrites and comments are an LLM session's job. A human normally
    touches only labels and metadata directly.
 
-3. **Comment a changelog, never a copy.** Every body rewrite gets one short
-   comment naming only what changed against the previous state - what is new,
-   what is gone, what was corrected. Do not snapshot the old body into a
-   comment: a full copy per revision forces a human to diff two prose texts,
-   which is not a readable history, only another copy.
+3. **Comment a changelog, never a copy.** A body rewrite gets one short comment
+   naming only what changed against the previous state - what is new, what is
+   gone, what was corrected. Do not snapshot the old body into a comment: a full
+   copy per revision forces a human to diff two prose texts, which is not a
+   readable history, only another copy.
+
+   One comment per *session's worth* of change, not per edit. Step 2 asks the
+   body to be kept current continuously, and a comment for every tick would bury
+   the board in noise; the changelog line summarises what that session moved.
+   Trivial upkeep - a typo, a tightened sentence - needs no comment at all.
 
    ```
    **Changelog:** Decision 2 tightened - `kind/` may now change over an
@@ -127,10 +155,46 @@ issues at that URL, which is exactly why `dist export` excludes
    answered can drop a size and move `kind/decision` to `kind/build`. Silent
    re-labelling is how a board stops meaning anything.
 
-7. **Close with what actually happened**, not with a commit hash alone: which
-   proposals were implemented, which were deliberately left out and why, and
-   what was verified. The issue is the only place that record survives - a
-   changelog entry says what changed, not what was decided against.
+7. **Closing is the last body update, not a comment.** If step 2 was followed
+   the body is already nearly there, and closing only settles what the final
+   run established. If it was not, closing is where the whole debt comes due -
+   and it comes due at the worst moment, because a closed body is the version
+   everyone reads afterwards and nobody revisits.
+
+   Either way the body reaches its final state *before* the issue closes:
+   proposals that were decided read as decided, a "to decide" section has become
+   the decision with its reasoning, acceptance criteria are ticked or struck with
+   a reason, and what was verified is named. Then close, with the one-line
+   changelog comment step 3 asks for.
+
+   Record what actually happened, not a commit hash alone: which proposals were
+   implemented, which were deliberately left out and why, and what was verified.
+   The issue is the only place that record survives - a changelog entry says
+   what changed, not what was decided against.
+
+   **A closing report in a comment does not satisfy this.** It reads as
+   complete to whoever writes it and leaves a body still phrased as open work:
+   unticked boxes, an undecided decision section, present tense about a defect
+   that no longer exists. #44 closed exactly that way, with a thorough comment
+   above a body that still asked for a decision that had already been made and
+   shipped. Nothing mechanical catches it (see below), which is why it is a step
+   rather than a habit.
+
+## What no tool checks
+
+`wikitool` does not know this tracker exists, and should not learn. It ships to
+instances that have no issues at that URL, while this file and the workflow it
+describes are pruned by `dist export` - a Gitea client inside the shipped tool
+would be a dev-only dependency carried by every instance, to check a board none
+of them have. The tracker is reachable only through the `gitea-mcp` server, in a
+session, by an agent.
+
+So there is no `docs verify` for the board. Nothing reports a closed issue whose
+body still reads as open, a body that contradicts its own comments, or an issue
+missing one of the four mandatory labels. Every one of those is caught by a
+session following this file, or not at all - which is the argument for the
+sequence in step 7 being explicit about the order (body first, then close),
+rather than leaving it to be inferred from step 2.
 
 ## Decision points
 
@@ -144,7 +208,8 @@ issues at that URL, which is exactly why `dist export` excludes
 - **Rewrite the body, or add a comment?** Rewrite whenever a reader of the body
   alone would otherwise be misled - a changed decision, a dropped criterion, a
   new constraint. A comment carries the changelog line for that rewrite, and
-  nothing else that a future session needs in order to act.
+  nothing else that a future session needs in order to act. Closing an issue is
+  always a rewrite - see step 7.
 - **An old issue carries only `prio/` and `size/`?** Complete it to all four
   when you touch it, rather than in a sweep. The board reaches the new scheme
   issue by issue, as each is picked up.

instructions/dev/stack-dev/SKILL.md

@@ -43,15 +43,21 @@ stack development happens in the origin repo instead (see AGENTS.md's routing li
    engineering, memory and deploy-time learning; consult before a design decision in those
    areas.
    [issue-tracking.md](../issue-tracking.md) - open work lives in Gitea issues, one per work
-   package, labelled `area/`, `kind/`, `prio/` and `size/`, with the body kept as the current
-   truth rather than as a first post. There is no `TODO.md`. Read it before filing something
-   for later, before editing an issue, or before deciding what to pick up next.
+   package, labelled `area/`, `kind/`, `prio/` and `size/`. There is no `TODO.md`. **The body
+   of the issue you are working on is this session's plan file:** keep it current as the state
+   moves, not at the end, so an interrupted session leaves a body the next one can resume from.
+   Read it before filing something for later, before editing or closing an issue, or before
+   deciding what to pick up next.
    [testing-conventions.md](../testing-conventions.md) - the suite runs against a deliberately
    empty machine; what the autouse fixture already neutralizes, and what a test still has to
    establish itself. Read it before adding or changing a test.
    [version-parts.md](../version-parts.md) - which part a change bumps: the drop-in test, the
    catalogue of breaks that cross the compatibility boundary with `kb/` untouched, and what to
    put in front of the user before a breaking bump. Read it before step 3.
+   [corpus-policy.md](../corpus-policy.md) - what "curated enough" means for the shared
+   demo/testbed `kb/`, the measurable floors that define it, and what a reactive fix may and may
+   not do to corpus content. Read it before judging whether the corpus can exercise a change, or
+   before any fix that would touch `kb/` content.
    More instructions are added here incrementally as stack-development needs come up - this
    list grows without needing this skill file to change shape.
 3. **Raise the version, if the change ships.** A change under `tools/`, `types/`,

instructions/dev/testing-conventions.md

@@ -40,6 +40,48 @@ resolved paths and `conventions`' parsed `kb/CONVENTIONS.md`. A test that *rewri
 conventions file mid-test calls `conventions.reset_cache()` itself - the fixture answers for the
 boundary between tests, not for one inside a test.
 
+## Which tree a test writes into
+
+The environment is one half of the isolation; `config.ROOT` is the other. With `CHEMENU_ROOT`
+cleared, `ROOT` falls back to the checkout pytest is running from - deliberately, because most
+tests want the shipped `types/`. It also means that any code path resolving a file through
+`config.ROOT` or `config.KB_DIR` reaches **the real repository**, no matter which tree the
+fixture built.
+
+Both corpus fixtures therefore repoint it: `raw_dir` and `kb_dir` each set
+`config.ROOT` to their `tmp_path` and re-declare the shipped `types/` through
+`use_shipped_type_specs()`. `config`'s module `__getattr__` resolves the derived paths on
+access, so repointing `ROOT` carries `KB_DIR`, `RAW_DIR` and the rest with it. A new fixture
+that builds a tree does the same thing - that is the rule here, not a per-test judgment.
+
+`kb_dir` did not, until Gitea #44. Two things came of that. A test calling
+`kb_state.write_kb_state()` overwrote the real `.wikitool-kb.json`, which `git status` made
+visible within the minute. Quieter and worse: `lint`'s collection lookup resolved a page
+against `config.KB_DIR`, so every fixture page read back as "no collection" and the
+`unauthorised_labels` check skipped every edge in silence - the finding had no working test at
+all, and its green run read like an assurance.
+
+Two guards came out of it, both in `conftest.py`:
+
+| Guard | Default | Cost |
+|---|---|---|
+| `repository_tree_guard` (session) | on | two `git status --porcelain` calls per run |
+| `per_test_tree_guard` | off, `CHEMENU_TREE_GUARD=each` turns it on | one `git status` per test |
+
+The session guard compares the working tree before against after and fails the run if anything
+moved, so it says nothing about uncommitted work a developer already had. It cannot name the
+test that did it; `CHEMENU_TREE_GUARD=each` can, and is the way to bisect once it fires. Where
+git is unavailable or the checkout is not a repository, both are silently inert.
+
+Neither guard sees the second, quieter half: a check that silently *does nothing* under test
+writes no file. That one is only caught by a test that asserts the finding actually fires -
+which is why `test_unauthorised_label_is_judged_in_a_tree_that_is_not_the_configured_kb`
+lints a tree `ROOT` deliberately points away from.
+
+**A function that takes a directory resolves against that directory.** `run_lint(kb_dir)`
+reading `config.KB_DIR` for one of its own lookups was the defect behind the quiet half, and
+no fixture can fix that shape from the outside.
+
 ## When to run
 
 Whenever you add or change a test under `tools/chemenu/tests/`.
@@ -80,7 +122,12 @@ Whenever you add or change a test under `tools/chemenu/tests/`.
    `conftest.py` in the same change. A variable the tool reads and the fixture does not clear
    is the exact hole this whole file is about, reopened.
 
-5. **Verify against an empty machine before publishing**, not only in your own shell:
+5. **Writing a fixture that builds a tree?** Repoint `config.ROOT` at it and call
+   `use_shipped_type_specs(monkeypatch)`, as `raw_dir` and `kb_dir` do - see
+   [Which tree a test writes into](#which-tree-a-test-writes-into). A fixture that returns a
+   path without repointing hands the code under test the real repository.
+
+6. **Verify against an empty machine before publishing**, not only in your own shell:
 
    ```bash
    cd tools && env -i PATH="$PATH" HOME="$(mktemp -d)" \
@@ -92,7 +139,7 @@ Whenever you add or change a test under `tools/chemenu/tests/`.
    `.venv/bin/python -m pytest -q`. A difference between the two is a leak, and the leaking
    variable belongs in step 4's list.
 
-6. **Check the coverage report when adding tests to close a gap**, rather than guessing which
+7. **Check the coverage report when adding tests to close a gap**, rather than guessing which
    lines were uncovered:
 
    ```bash

instructions/kb-profiles.md

@@ -68,7 +68,7 @@ stack's hardcoded behaviour until the conventions file existed.
 |---|---|
 | `language:` | `de` |
 | `sections:` | `Beziehungen` / `Siehe auch` / `Fußnoten` |
-| Naming | Human-readable titles with spaces; singular for entities; `adr-NNN-` for decisions; `X vs Y` for comparisons |
+| Naming | Human-readable titles with spaces; singular for entities; a decision named like any other concept, no `adr-NNN-` prefix; `X vs Y` for comparisons |
 | Tone | Wikipedia register, with a German buzzword and filler list |
 | Relationship labels | `hängt ab von` · `verwendet` · `implementiert` · `erweitert` · `ersetzt` · `steht in Konflikt mit` · `benötigt` · `erzeugt` · `konsumiert` · `besitzt` · `pflegt` · `läuft auf` · `verwandt mit` |
 | Confidence rubric | 0.5 base, +0.2 per supporting source (max +0.6), recency and source-quality bonuses; hedge with "möglicherweise"/"kann" below 0.6, "unsicher"/"unbestätigt" below 0.4 |

kb/CONVENTIONS.md

@@ -62,7 +62,8 @@ There is no `## Siehe auch` region any more. It was the reciprocal half of a bid
 - Human-readable titles with spaces: `Hybrid Search.md`, `Gitea Actions.md` - not kebab-case.
 - Singular for entities: `ha-core.md`, not `ha-cores.md`.
 - Comparison pages read as a comparison: `Go vs Rust.md`.
-- ADRs are prefixed: `adr-001-use-go-modules.md`.
+- A decision (`concept_type: decision`) is named like any other concept - no `adr-NNN-` prefix.
+  See [kb/concepts/COLLECTION.md § Decisions](concepts/COLLECTION.md#decisions).
 - Prefer readability over convention when the two conflict.
 
 What to name a thing: projects use their repository or common name; systems a descriptive

kb/concepts/COLLECTION.md

@@ -27,19 +27,27 @@ tone, relationship labels, the confidence rubric. Neither is restated here.
 
 `concept` (`tools/wikitool types describe concept`).
 
-## Decisions and ADRs
+## Decisions
 
-An architectural decision is a concept page, prefixed as
-[kb/CONVENTIONS.md § Naming](../CONVENTIONS.md#naming) says. It records:
+An architectural decision is an ordinary concept page with `concept_type: decision`
+(`tools/wikitool types describe concept`) - not a separate format, and not a separate location.
+There is no `adr-NNN-`-prefixed filename and no dedicated directory: naming follows
+[kb/CONVENTIONS.md § Naming](../CONVENTIONS.md#naming) like every other concept, and the page
+lives in `kb/concepts/` like every other concept.
 
-- **Context** - what forced a decision.
-- **Decision** - what was chosen.
-- **Consequences** - what this costs, not only what it buys.
-- **Status** - proposed / accepted / deprecated / superseded.
-- Links to every entity the decision affects.
+The body is organic prose under this collection's usual sections, not a fixed template. What it
+still has to carry: what was decided, what forced the decision, what it costs (not only what it
+buys), and a link to every entity the decision affects. A `**Status:**` line is optional - most
+decision pages in this instance carry none, because the page's own prose already says whether the
+decision stands.
 
-A superseded ADR is never deleted or rewritten. The new one declares `supersedes` pointing at
-it; the old one needs no edge back, because its inbound view renders the replacement.
+A decision superseded by a later one is never deleted or rewritten. The new page declares
+`supersedes` pointing at it; the old one needs no edge back, because its inbound view renders the
+replacement.
+
+`concept_type: decision` is also the one subtype [kb/CONTRACT.md](../CONTRACT.md)'s confidence
+machinery treats differently: `confidence decay` skips it structurally, because elapsed time does
+not falsify a decision - only a later decision superseding it does.
 
 ## Authorised labels
 

tools/CONTRACT.md

@@ -68,10 +68,10 @@ tools/wikitool <command> --help
 | `instructions sync [--force]` | Publish every `instructions/<name>/SKILL.md` into `.agents/skills/` and `.claude/skills/` as **copies**, and delete published skills whose source is gone. Both targets are gitignored, so a fresh clone runs this once - see `instructions/bootstrap.md`. Re-running is also how a drifted copy is repaired: the source always wins. `--force` is required only to replace a target directory that is not a published skill at all (no `SKILL.md` in it) |
 | `instructions verify` | Check the instruction layer: flat instructions validate against `types/instruction.schema.yaml`, each `SKILL.md` carries the frontmatter its harness reads, every published copy is byte-identical to its source, no instruction is left that nothing references, and nothing under `instructions/dev/` is referenced from outside it (a `<!-- dist:strip-start/end -->` block is exempt - see [instructions/CONTRACT.md](../instructions/CONTRACT.md)). Missing *every* copy is reported as "run sync", not as drift - that is a clean checkout |
 | `instructions list [--json]` | List the flat instructions with their descriptions. This is how the layer is discovered; `search` deliberately covers `kb/` only |
-| `docs verify` | Check the docs that mirror the code: every CLI command documented here (and vice versa), every directory under `kb/` has a `COLLECTION.md` and no directory outside it does, every collection declaring `profile:` and a `required_by_stack:` that agrees with the stack's own list, `kb/CONVENTIONS.md` naming all three tool-owned section headings if it exists at all, every stage contract present, no pre-migration `type: entity` blocks left in the contracts, and the `.gitignore` canaries clear in both directions (nothing ignored under `raw/`/`kb/`, everything ignored under `reports/` and the published skill directories) |
+| `docs verify` | Check the docs that mirror the code: every CLI command documented here (and vice versa), every directory under `kb/` has a `COLLECTION.md` and no directory outside it does, every collection declaring `profile:` and a `required_by_stack:` that agrees with the stack's own list, `kb/CONVENTIONS.md` naming all three tool-owned section headings if it exists at all, every stage contract present, no pre-migration `type: entity` blocks left in the contracts, and the `.gitignore` canaries clear in both directions (nothing ignored under `raw/`/`kb/`, everything ignored under `reports/` and the published skill directories). The name is about documentation parity, not about the `docs/` directory - it neither reads nor requires one, the same way `kb/` predates the collection it now checks |
 | `eval sessions [--json]` | List the sessions that have a trace under `reports/telemetry/`, most recent first. Read-only and exempt from the Iteration Budget Gate |
 | `eval score [--session <id>] [--json] [--markdown out.md] [--save] [--fail-on-error]` | Score one traced session: structural state from `lint`'s own checks (L1) plus trajectory rules over the trace (L2) - was a refused call repeated unchanged, was a gate flag passed without that gate having refused anything, did a publish of `kb/` pages go unlogged. Defaults to the current session. `--save` writes `reports/evals/<date>/<session>.{json,md}`. Read-only over `kb/` and exempt from the budget; see [../EVALS.md](../EVALS.md) |
-| `dist export <target> [--dry-run] [--source-repo U] [--source-commit SHA] [--release-url U] [--update-url U]` | Write a contentless, distributable copy of this repo's machinery into an empty `<target>` directory: `AGENTS.md`/`README.md`/`EVALS.md` with any `<!-- dist:strip-start -->...<!-- dist:strip-end -->` region removed, `instructions/` (minus `instructions/dev/`), `types/` (the `root: kb` page type-specs and their schemas re-keyed as `.template`, the stack's own verbatim), `tools/` (no venv/caches), the `.github/hooks/`+`.vibe/` session-tracing config plus `.claude/settings.json`, `kb/CONTRACT.md` (no pages, no areas), empty `raw/{articles,documents,notes,assets}/`, `VERSION`, `USER.md.template`/`SOUL.md.template` plus `kb/CONVENTIONS.md.template` and each collection's contract re-keyed as `kb/<name>/COLLECTION.md.template` (the templates ship; the filled `USER.md`/`SOUL.md`/`kb/CONVENTIONS.md`/`kb/<name>/COLLECTION.md`/`types/<page-type>.md` never do - all of them bind their instance and none are the stack's to decide, and `find_leaks` refuses a plan carrying one), and a generated `.wikitool-release.json` stamp (version, export date, origin, and a sha256 per exported file - the base a later upgrade would compare against). The four origin options only fill stamp fields: `export` never calls git and cannot discover them. Refuses a non-empty target, and a tree with no `VERSION`. See `instructions/setup-instance.md`. One-way: there is no command that reconstructs a distributed instance into a dev instance - work on the stack in the origin repo (or a new dev instance exported from it) instead |
+| `dist export <target> [--dry-run] [--source-repo U] [--source-commit SHA] [--release-url U] [--update-url U]` | Write a contentless, distributable copy of this repo's machinery into an empty `<target>` directory: `AGENTS.md`/`README.md`/`EVALS.md` with any `<!-- dist:strip-start -->...<!-- dist:strip-end -->` region removed, `instructions/` (minus `instructions/dev/`), `types/` (the `root: kb` page type-specs and their schemas re-keyed as `.template`, the stack's own verbatim), `docs/` verbatim, `tools/` (no venv/caches), the `.github/hooks/`+`.vibe/` session-tracing config plus `.claude/settings.json`, `kb/CONTRACT.md` (no pages, no areas), empty `raw/{articles,documents,notes,assets}/`, `VERSION`, `USER.md.template`/`SOUL.md.template` plus `kb/CONVENTIONS.md.template` and each collection's contract re-keyed as `kb/<name>/COLLECTION.md.template` (the templates ship; the filled `USER.md`/`SOUL.md`/`kb/CONVENTIONS.md`/`kb/<name>/COLLECTION.md`/`types/<page-type>.md` never do - all of them bind their instance and none are the stack's to decide, and `find_leaks` refuses a plan carrying one), and a generated `.wikitool-release.json` stamp (version, export date, origin, and a sha256 per exported file - the base a later upgrade would compare against). The four origin options only fill stamp fields: `export` never calls git and cannot discover them. Refuses a non-empty target, and a tree with no `VERSION`. See `instructions/setup-instance.md`. One-way: there is no command that reconstructs a distributed instance into a dev instance - work on the stack in the origin repo (or a new dev instance exported from it) instead |
 | `version show [--json]` | Print this instance's stack version and where it came from (development tree, or a distribution with its export date and origin). Bare `wikitool version` is an alias for this. Read-only, offline, and **exempt from the Iteration Budget Gate** |
 | `version check [--url U] [--timeout S] [--json]` | Ask the origin's release feed whether a newer stack exists, and whether the step crosses a compatibility boundary (`state: current\|update\|migration\|ahead`). **The only command in `wikitool` that makes a network call** - never reached implicitly from another command, needs no key, times out, and reports an unreachable feed as an error rather than as "up to date". The feed is `$WIKITOOL_UPDATE_URL`, else the release stamp's, else the built-in origin; `$WIKITOOL_UPDATE_TOKEN` is only needed if that feed is not readable anonymously. Read-only and exempt from the budget gate |
 | `version notes [--version X.Y.Z]` | Print one version's `CHANGES.md` entry, for use as release notes (default: this tree's `VERSION`). Read-only and exempt from the budget gate |

tools/chemenu/commands/confidence_decay.py

@@ -11,6 +11,14 @@ Keeping the undecayed anchor in `confidence_base` is what makes repeated runs
 idempotent - decaying the stored `confidence` in place (the pre-2026-08-13
 behavior) compounded on every run, because the elapsed-months factor kept
 growing while the multiplicand had already shrunk.
+
+Pages with `concept_type: decision` are skipped structurally, not as an
+interim measure. The formula models staleness - a claim that nobody has
+re-checked in a while becomes less trustworthy - and a decision is not a
+claim about the world that time can falsify. What retires a decision is a
+later decision superseding it, never elapsed months on its own; that is a
+category the decay formula does not have a term for, so it does not apply
+one.
 """
 from __future__ import annotations
 
@@ -118,6 +126,8 @@ def confidence_decay(
     missing_base = []
 
     for title, page in sorted(pages.items()):
+        if page.frontmatter.get("concept_type") == "decision":
+            continue
         confidence = page.frontmatter.get("confidence")
         if confidence is None:
             continue

tools/chemenu/commands/dist_cmd.py

@@ -347,6 +347,12 @@ def build_plan(origin: Optional[Origin] = None) -> dict[str, PlannedFile]:
     for hook_dir in HOOK_DIRS:
         plan.update(_copy_tree(config.ROOT / hook_dir, hook_dir, frozenset()))
 
+    # docs/ is stack background - why the stack is built the way it is - and
+    # ships verbatim like instructions/ and types/: it carries no page, no
+    # frontmatter, and (AGENTS.md § File naming) no normative sentence, so
+    # there is nothing instance-owned in it to split off as a .template.
+    plan.update(_copy_tree(config.ROOT / "docs", "docs", frozenset()))
+
     # `kb/CONTRACT.md` is stack-owned and ships verbatim; everything beside it
     # under `kb/` is the instance's own and ships only as a `.template`. That is
     # the personalization split (`USER.md`/`SOUL.md`) one directory down, and
@@ -492,7 +498,8 @@ def export_command(
 ):
     """Export a contentless, distributable copy of this repo's machinery:
     AGENTS.md/README.md (dev-instance-only marker blocks removed),
-    instructions/ (no instructions/dev/), types/, tools/ (no venv/caches),
+    instructions/ (no instructions/dev/), types/, docs/ verbatim,
+    tools/ (no venv/caches),
     the .github/hooks/+.vibe session-tracing config plus .claude/settings.json,
     kb/CONTRACT.md plus a COLLECTION.md.template per collection and
     kb/CONVENTIONS.md.template (no pages, no areas), empty

tools/chemenu/lint_core.py

@@ -165,9 +165,15 @@ def run_lint(kb_dir: Path) -> dict:
     # propagated, a deleted page, or a URL pasted where a title belongs - used
     # to pass every check. Which fields hold page titles is declared by each
     # type-spec's `page_ref_fields:`, not hardcoded here.
+    # Resolved against the directory `run_lint()` was handed, not against
+    # `config.KB_DIR`. A page under a tree that is not the configured corpus -
+    # every fixture tree, and any `lint <path>` aimed elsewhere - raised
+    # `ValueError` here and read as "no collection", which made the label
+    # authorisation below skip the edge in silence rather than judge it
+    # (Gitea #44).
     def _collection_of(page):
         try:
-            return page.path.relative_to(config.KB_DIR).parts[0]
+            return page.path.relative_to(kb_dir).parts[0]
         except (ValueError, IndexError):
             return None
 
@@ -211,7 +217,9 @@ def run_lint(kb_dir: Path) -> dict:
                 destination = _collection_of(target_page)
                 if destination is None:
                     continue
-                allowed = kb_collections.authorised_labels(source_collection, destination)
+                allowed = kb_collections.authorised_labels(
+                    source_collection, destination, kb_dir
+                )
                 if edge.label not in allowed:
                     unauthorised_labels.append(
                         {

tools/chemenu/tests/conftest.py

@@ -1,4 +1,5 @@
 import os
+import subprocess
 from pathlib import Path
 
 import pytest
@@ -37,6 +38,78 @@ _GIT_ENV = (
 )
 
 
+def _working_tree_state() -> str | None:
+    """`git status --porcelain` for the checkout the tests live in, or None if
+    there is no git available to ask."""
+    try:
+        result = subprocess.run(
+            ["git", "-C", str(config._PACKAGE_ROOT), "status", "--porcelain"],
+            capture_output=True,
+            text=True,
+            timeout=60,
+        )
+    except (OSError, subprocess.SubprocessError):
+        return None
+    return result.stdout if result.returncode == 0 else None
+
+
+_TREE_GUARD_MESSAGE = (
+    "A test wrote into the repository checkout instead of into its tmp_path.\n"
+    "`git status --porcelain` moved while the suite ran:\n\n"
+    "  before:\n{before}\n"
+    "  after:\n{after}\n\n"
+    "This is the class of bug Gitea #44 describes: code under test resolves a "
+    "path through `config.ROOT`/`config.KB_DIR` rather than through the "
+    "directory the fixture handed it, so the write lands in the real tree. Fix "
+    "the fixture (repoint `config.ROOT`, as `raw_dir` and `kb_dir` do) or the "
+    "code path, never the symptom.\n"
+    "To find the test that did it, re-run with CHEMENU_TREE_GUARD=each - the "
+    "guard then checks after every test and fails on the first one that moves "
+    "the tree."
+)
+
+
+@pytest.fixture(scope="session", autouse=True)
+def repository_tree_guard():
+    """Fail the run if the suite moved a file in the real checkout.
+
+    Two `git status` calls for the whole session, which is why this is on by
+    default: it catches the whole class rather than the one case that was
+    noticed. It compares before against after rather than demanding a clean
+    tree, so it says nothing about a developer's own uncommitted work.
+
+    It cannot name the culprit - set `CHEMENU_TREE_GUARD=each` for that, which
+    trades a `git status` per test for a failure on the test that did it.
+    """
+    before = _working_tree_state()
+    yield
+    after = _working_tree_state()
+    if before is None or after is None or before == after:
+        return
+    raise AssertionError(
+        _TREE_GUARD_MESSAGE.format(before=before or "(clean)", after=after or "(clean)")
+    )
+
+
+@pytest.fixture(autouse=True)
+def per_test_tree_guard(repository_tree_guard):
+    """The bisect half of `repository_tree_guard`, off unless asked for.
+
+    `CHEMENU_TREE_GUARD=each` turns the session-wide "something moved the tree"
+    into "this test moved the tree", at the cost of a `git status` per test.
+    """
+    if os.environ.get("CHEMENU_TREE_GUARD") != "each":
+        yield
+        return
+    before = _working_tree_state()
+    yield
+    after = _working_tree_state()
+    if before is not None and after is not None and before != after:
+        raise AssertionError(
+            _TREE_GUARD_MESSAGE.format(before=before or "(clean)", after=after or "(clean)")
+        )
+
+
 @pytest.fixture(autouse=True)
 def hermetic_environment(tmp_path: Path, monkeypatch: pytest.MonkeyPatch):
     """Cut every test off from the machine it runs on.
@@ -159,13 +232,25 @@ def raw_dir(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> Path:
 
 
 @pytest.fixture
-def kb_dir(tmp_path: Path) -> Path:
+def kb_dir(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> Path:
     """A minimal fixture kb/ with the standard collection layout, populated
     with a handful of pages covering entities/concepts/sources/comparisons.
 
     Every collection carries a COLLECTION.md, both because that is what makes it
     a collection and because the scanner must prove it skips them at a depth the
-    kb-root meta files never reach."""
+    kb-root meta files never reach.
+
+    `config.ROOT` is repointed for the same reason `raw_dir` does it, one
+    collection over: code under test that resolves a path through
+    `config.ROOT`/`config.KB_DIR` rather than through the directory it was
+    handed otherwise reaches the *real* repository. That was not theoretical
+    either - a test calling `kb_state.write_kb_state()` overwrote this
+    checkout's `.wikitool-kb.json`, and `lint`'s collection lookup answered
+    "no collection" for every fixture page, which left `unauthorised_labels`
+    with no working test at all (Gitea #44).
+    """
+    monkeypatch.setattr(config, "ROOT", tmp_path)
+    use_shipped_type_specs(monkeypatch)
     kb = tmp_path / "kb"
     for sub in ("entities/projects", "entities/systems", "entities/tools",
                 "entities/technologies", "entities/people",

tools/chemenu/tests/test_confidence_decay.py

@@ -5,7 +5,7 @@ import pytest
 from chemenu import config
 from chemenu.commands import confidence_decay
 from chemenu.commands.confidence_decay import FLOOR, compute_decay
-from chemenu.frontmatter_io import read_page
+from chemenu.frontmatter_io import read_page, write_page
 
 
 def test_no_decay_at_zero_months():
@@ -68,3 +68,22 @@ def test_decay_skips_pages_without_a_base(decay_wiki):
     confidence_decay.confidence_decay(apply=True)
     frontmatter, _ = read_page(decay_wiki / "entities/systems/aurora.md")
     assert frontmatter["confidence"] == 0.9
+
+
+def test_decay_skips_decision_pages(decay_wiki):
+    """A decision is not falsified by elapsed time, only by a later decision
+    superseding it - `concept_type: decision` is a categorical skip, not
+    something an old `modified` date should ever decay (Gitea #38)."""
+    decision_path = decay_wiki / "concepts" / "some-decision.md"
+    write_page(
+        decision_path,
+        {
+            "type": "types/concept.md", "concept_type": "decision",
+            "tags": [], "created": "2015-01-01", "modified": "2015-01-01",
+            "related": [], "sources": [], "confidence": 0.9, "confidence_base": 0.9,
+        },
+        "\n# some-decision\n",
+    )
+    confidence_decay.confidence_decay(apply=True)
+    frontmatter, _ = read_page(decision_path)
+    assert frontmatter["confidence"] == 0.9

tools/chemenu/tests/test_dist_cmd.py

@@ -135,6 +135,10 @@ def repo(tmp_path: Path, monkeypatch: pytest.MonkeyPatch) -> Path:
         f"<!-- {config.TEMPLATE_SENTINEL} -->\n# conventions template\n", encoding="utf-8"
     )
 
+    docs_dir = root / "docs"
+    docs_dir.mkdir()
+    (docs_dir / "why-gates-are-code.md").write_text("# Why gates are code\n", encoding="utf-8")
+
     for relative in ("raw/CONTRACT.md", "reports/CONTRACT.md", "work/CONTRACT.md"):
         path = root / relative
         path.parent.mkdir(parents=True, exist_ok=True)
@@ -156,6 +160,11 @@ def test_plan_never_includes_commonplace(repo):
     assert "commonplace" not in combined
 
 
+def test_plan_ships_docs_verbatim(repo):
+    plan = dist_cmd.build_plan()
+    assert plan["docs/why-gates-are-code.md"].content == "# Why gates are code\n"
+
+
 def test_plan_never_includes_instructions_dev(repo):
     """instructions/dev/ - flat dev-only instructions and the nested skill
     that switches a session into tool-development mode - is pruned

tools/chemenu/tests/test_hermetic_env.py

@@ -74,3 +74,23 @@ def test_wiki_author_overrides_the_git_identity(tmp_path: Path,
     monkeypatch.setattr(config, "ROOT", tmp_path)
     monkeypatch.setenv("WIKI_AUTHOR", "Env Override")
     assert config.default_author() == "Env Override"
+
+
+def test_kb_dir_repoints_the_configured_root_at_its_own_tree(kb_dir: Path, tmp_path: Path):
+    """The other half of the isolation, and the one `kb_dir` was missing until
+    Gitea #44: a fixture that builds a corpus but leaves `config.ROOT` on the
+    real checkout hands every `config.KB_DIR` lookup the developer's own wiki -
+    which is how a test overwrote the repository's `.wikitool-kb.json`."""
+    assert config.ROOT == tmp_path
+    assert config.KB_DIR == kb_dir
+
+
+def test_raw_dir_repoints_the_configured_root_at_its_own_tree(raw_dir: Path, tmp_path: Path):
+    assert config.ROOT == tmp_path
+    assert config.RAW_DIR == raw_dir
+
+
+def test_both_corpus_fixtures_keep_the_shipped_type_specs_reachable(kb_dir: Path):
+    """Repointing `ROOT` moves `TYPES_DIR` with it, so the repoint has to be
+    paired with `use_shipped_type_specs()` or no page type resolves at all."""
+    assert (config.TYPES_DIR / "entity.md").is_file()

tools/chemenu/tests/test_lint.py

@@ -15,7 +15,6 @@ from chemenu.commands.lint import (
 )
 from chemenu.frontmatter_io import write_page
 from chemenu.provenance import cite_id, render_cite_block
-from chemenu.tests.conftest import use_shipped_type_specs
 from chemenu.version import Version
 
 
@@ -482,26 +481,18 @@ def test_lint_does_not_count_a_shell_prompt_as_a_quote(kb_dir):
 
 # --- the migration gate on `unlabelled_edges` / `unauthorised_labels` -------
 #
-# These four repoint `config.ROOT` at the fixture tree, which the `kb_dir`
-# fixture alone does not do. Two things need it: `write_kb_state()` writes
-# `.wikitool-kb.json` relative to `ROOT`, and `lint`'s collection lookup
-# resolves a page against `config.KB_DIR` rather than against the directory it
-# was handed - so without the repoint the gate would be read off the real
-# repository's state file.
+# These read and write `.wikitool-kb.json`, which `kb_state` resolves relative
+# to `config.ROOT`. The `kb_dir` fixture repoints `ROOT` at its own tmp_path
+# (Gitea #44), so the gate is read off the fixture tree; before it did, these
+# four ran against the real repository's state file and one of them overwrote
+# it.
 
 
-@pytest.fixture
-def rooted_kb(kb_dir, tmp_path, monkeypatch):
-    monkeypatch.setattr(config, "ROOT", tmp_path)
-    use_shipped_type_specs(monkeypatch)
-    return kb_dir
-
-
-def _page_with_an_unlabelled_edge(rooted_kb):
+def _page_with_an_unlabelled_edge(kb_dir):
     """A `related:` entry that is a bare title rather than a `label: title`
     mapping - the shape every page was in before the 4.0.0 migration."""
     write_page(
-        rooted_kb / "entities/tools/bare-edge.md",
+        kb_dir / "entities/tools/bare-edge.md",
         {"type": "types/entity.md", "entity_type": "tool", "tags": [], "created": "2026-09-03",
          "modified": "2026-09-03", "related": ["Modbus"], "sources": [], "confidence": 0.8,
          "provenance": "general", "summary": "One edge whose label was never declared."},
@@ -509,14 +500,14 @@ def _page_with_an_unlabelled_edge(rooted_kb):
     )
 
 
-def test_unlabelled_edge_is_advisory_below_kb_version_4(rooted_kb):
+def test_unlabelled_edge_is_advisory_below_kb_version_4(kb_dir):
     """The window the migration document describes: the machinery has landed,
     the corpus has not been converted yet, and `lint --fail-on-error` must not
     refuse the very tree the migration tells the instance to publish unit by
     unit."""
-    _page_with_an_unlabelled_edge(rooted_kb)
+    _page_with_an_unlabelled_edge(kb_dir)
     kb_state.write_kb_state(Version(3, 0, 0), [])
-    report = run_lint(rooted_kb)
+    report = run_lint(kb_dir)
     assert report["unlabelled_edges"] != []
     assert "unlabelled_edges" not in hard_error_keys()
     # Narrowed to the finding under test: the fixture corpus carries unrelated
@@ -525,34 +516,64 @@ def test_unlabelled_edge_is_advisory_below_kb_version_4(rooted_kb):
     assert has_hard_errors({"unlabelled_edges": report["unlabelled_edges"]}) is False
 
 
-def test_unlabelled_edge_is_hard_at_kb_version_4(rooted_kb):
+def test_unlabelled_edge_is_hard_at_kb_version_4(kb_dir):
     """Once the migration is recorded, a bare title is no longer a page waiting
     its turn - it is an edge whose author did not say what it asserts."""
-    _page_with_an_unlabelled_edge(rooted_kb)
+    _page_with_an_unlabelled_edge(kb_dir)
     kb_state.write_kb_state(Version(4, 0, 0), [])
-    report = run_lint(rooted_kb)
+    report = run_lint(kb_dir)
     assert report["unlabelled_edges"] != []
     assert "unlabelled_edges" in hard_error_keys()
     assert has_hard_errors({"unlabelled_edges": report["unlabelled_edges"]}) is True
 
 
-def test_unauthorised_label_is_hard_at_kb_version_4(rooted_kb):
+def test_unauthorised_label_is_hard_at_kb_version_4(kb_dir):
     """The fixture contracts authorise `depends-on` but not `contradicts`."""
     write_page(
-        rooted_kb / "entities/tools/off-menu.md",
+        kb_dir / "entities/tools/off-menu.md",
         {"type": "types/entity.md", "entity_type": "tool", "tags": [], "created": "2026-09-03",
          "modified": "2026-09-03", "related": [{"contradicts": "Modbus"}], "sources": [],
          "confidence": 0.8, "provenance": "general", "summary": "A label off this menu."},
         "\n# off-menu\n\nA label the source collection never authorised.\n",
     )
     kb_state.write_kb_state(Version(4, 0, 0), [])
-    report = run_lint(rooted_kb)
+    report = run_lint(kb_dir)
     assert report["unauthorised_labels"] != []
     assert "unauthorised_labels" in hard_error_keys()
     assert has_hard_errors({"unauthorised_labels": report["unauthorised_labels"]}) is True
 
 
-def test_a_tree_that_never_declared_a_kb_version_keeps_every_key(rooted_kb):
+def test_unauthorised_label_is_judged_in_a_tree_that_is_not_the_configured_kb(
+    kb_dir, tmp_path, monkeypatch
+):
+    """`run_lint()` judges the tree it was handed, not the configured corpus.
+
+    The collection lookup used to resolve a page against `config.KB_DIR`; a
+    page anywhere else raised `ValueError`, read back as "no collection", and
+    the label check skipped the edge without a word. That is why
+    `unauthorised_labels` was untested in practice before Gitea #44 - every
+    fixture tree was somewhere else. Here `ROOT` deliberately points away from
+    the tree under lint, which is the case the old code got wrong.
+    """
+    write_page(
+        kb_dir / "entities/tools/off-menu.md",
+        {"type": "types/entity.md", "entity_type": "tool", "tags": [], "created": "2026-09-03",
+         "modified": "2026-09-03", "related": [{"contradicts": "Modbus"}], "sources": [],
+         "confidence": 0.8, "provenance": "general", "summary": "A label off this menu."},
+        "\n# off-menu\n\nA label the source collection never authorised.\n",
+    )
+    elsewhere = tmp_path / "elsewhere"
+    elsewhere.mkdir()
+    monkeypatch.setattr(config, "ROOT", elsewhere)
+    assert config.KB_DIR != kb_dir
+
+    report = run_lint(kb_dir)
+    assert {
+        "page": "off-menu", "target": "Modbus", "label": "contradicts", "destination": "concepts"
+    } in report["unauthorised_labels"]
+
+
+def test_a_tree_that_never_declared_a_kb_version_keeps_every_key(kb_dir):
     """No `.wikitool-kb.json` means a fresh instance, which starts at the
     current shape rather than migrating into it - so there is no outstanding
     migration for a gated finding to be the noise of."""