docs: make the resolution contract match what the gate actually does

Both AGENTS.md and ADR-0020 said deployed .claude/.agents trees are consulted "only
when no authoring root exists". That stopped being true in f7cc279: the walk-up
finds a root in any git repo, so the condition is now whether that root holds
plugins, not whether one was found at all. Left alone, the two documents describe a
resolver that no longer exists — and this repo's prose is load-bearing, since the
next agent reads it instead of the code.

Both now also record why a name-count delta is not an equivalent test, because it is
the obvious simplification and it is wrong: a single-plugin monorepo re-collects its
own package, adds no new name, and would pull the deployed trees back in.

ADR: 0020

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015W3iwF9ncfRZddGBxsMCYi

AGENTS.md

@@ -44,7 +44,7 @@ Fall back to raw shell only when no skill covers it.
 - Install the `apm` CLI — four pre-push hooks shell out to it: `apm-marketplace-check`, `apm-audit-ci`, `apm-pack-check-clean`, and `check-plugin-content-sync` (via `scripts/sync-plugin-content.sh`, which wraps `apm pack`). `apm-marketplace-check` and `apm-pack-check-clean` are bare `apm …` hook entries and `apm-audit-ci` is a `bash -c` loop calling `apm` once per package, so without it the push dies with an unhelpful "command not found". Use `apm-install`, or `curl -sSL https://aka.ms/apm-unix | sh`; verify with `apm --version`.
 - Install `jq` — required by `scripts/check-manifests.sh` and `scripts/sync-plugin-content.sh`, both pre-push. These at least fail loudly (`Error: jq is required but not installed`).
 - Install `python3` — required by `scripts/skill-size-check.sh`, the `skill-size-check` pre-commit hook. It measures the *folded* `description` value: most descriptions here are `>`-block scalars, so a regex over the raw lines measures indentation and newlines instead of the value. Missing it fails the hook with an install pointer rather than skipping the ADR-0020 checks, which would be a vacuous green. In practice it is already present — pre-commit is itself a Python application. **PyYAML is a hard requirement too**, not an optional accelerator: the hand-rolled fallback frontmatter reader has been removed, because a reader that mis-parses an unfamiliar scalar shape reports a clean pass on a file it never measured, which is the exact vacuous-green failure the `python3` check exists to avoid. `pip install pyyaml` if the hook reports it missing.
-- That hook enforces **two independent gate families** over `plugins/*/.apm/skills/*/SKILL.md`, and neither replaced the other. The agentskills.io spec backstop is unchanged: 500 lines and 2,770 words, counted over the **whole file including frontmatter**. ADR-0020 adds a context budget measured differently — `description` 250 chars SUGGESTION / 400 FAIL (it is preloaded into every session whether the skill fires or not), **body-only** word count 600 SUGGESTION / 900 FAIL (everything after the frontmatter's closing `---`), a missing, valueless or `null` `description:` (a hard FAIL, not a skip — a gate that declines to measure the one preloaded field reports green), every boundary-clause routing target resolving to a real skill or agent, and every `references/<file>.md` a body names actually existing. Target resolution walks up **from the file being checked** to an authoring root — the nearest ancestor holding `plugins/*/.apm/{skills,agents}`, falling back to the nearest `.git`, in two passes so a nested `.git` cannot beat a real monorepo root. The universe is then every skill and agent under `<root>/plugins/*/`, plus the checked file's own apm package and whatever that package declares in its own `apm.yml` `dependencies.apm`; the **root** manifest's `dependencies:` block is not read, and no plugin here declares a cross-plugin apm dependency. Deployed `.claude/`/`.agents/` trees are consulted only when no authoring root exists — the consumer case. That matters because those trees are gitignored `apm install` output: resolution used to reach the four cross-plugin `gitea-*` → `git-*` targets through `.claude/skills/` alone, so the same commit measured 2 dangling targets on a developer machine and 6 on a fresh clone. It no longer does — verified by running the hook over a tree holding only `plugins/` and the root `apm.yml`, which reports findings identical to the working tree (26 description / 9 body / 2 dangling / 0 missing references / 58 SUGGESTIONs). Three further checks are SUGGESTION-only: a description with no boundary clause at all, a `## Gotchas` section with more than five entries, and a `## Gotchas` section over 25% of the body. A file can sit well inside one family and fail the other. The hook is `verbose: true` so the SUGGESTION tier is audible — pre-commit prints nothing at all for a passing hook, and a SUGGESTION deliberately does not fail. `skill-audit`'s `validate.sh` holds a second copy of the four ADR-0020 constants; `tests/test-skill-size-check.sh` asserts the copies agree.
+- That hook enforces **two independent gate families** over `plugins/*/.apm/skills/*/SKILL.md`, and neither replaced the other. The agentskills.io spec backstop is unchanged: 500 lines and 2,770 words, counted over the **whole file including frontmatter**. ADR-0020 adds a context budget measured differently — `description` 250 chars SUGGESTION / 400 FAIL (it is preloaded into every session whether the skill fires or not), **body-only** word count 600 SUGGESTION / 900 FAIL (everything after the frontmatter's closing `---`), a missing, valueless or `null` `description:` (a hard FAIL, not a skip — a gate that declines to measure the one preloaded field reports green), every boundary-clause routing target resolving to a real skill or agent, and every `references/<file>.md` a body names actually existing. Target resolution walks up **from the file being checked** to an authoring root — the nearest ancestor holding `plugins/*/.apm/{skills,agents}`, falling back to the nearest `.git`, in two passes so a nested `.git` cannot beat a real monorepo root. The universe is then every skill and agent under `<root>/plugins/*/`, plus the checked file's own apm package and whatever that package declares in its own `apm.yml` `dependencies.apm`; the **root** manifest's `dependencies:` block is not read, and no plugin here declares a cross-plugin apm dependency. Deployed `.claude/`/`.agents/` trees are consulted only when the walk found no plugin monorepo root — whether it landed on a bare `.git` ancestor or on nothing at all (the consumer case). The gate keys on which of the two passes matched, not on whether the root contributed any new name: a single-plugin monorepo re-collects its own package and adds nothing, so a name-count test reads zero there and would drag the deployed trees back into the universe. That matters because those trees are gitignored `apm install` output: resolution used to reach the four cross-plugin `gitea-*` → `git-*` targets through `.claude/skills/` alone, so the same commit measured 2 dangling targets on a developer machine and 6 on a fresh clone. It no longer does — verified by running the hook over a tree holding only `plugins/` and the root `apm.yml`, which reports findings identical to the working tree (26 description / 9 body / 2 dangling / 0 missing references / 58 SUGGESTIONs). Three further checks are SUGGESTION-only: a description with no boundary clause at all, a `## Gotchas` section with more than five entries, and a `## Gotchas` section over 25% of the body. A file can sit well inside one family and fail the other. The hook is `verbose: true` so the SUGGESTION tier is audible — pre-commit prints nothing at all for a passing hook, and a SUGGESTION deliberately does not fail. `skill-audit`'s `validate.sh` holds a second copy of the four ADR-0020 constants; `tests/test-skill-size-check.sh` asserts the copies agree.
 - **Those ADR-0020 gates ship hot, with no baseline file.** 26 of 39 descriptions and 9 of 39 bodies currently exceed their FAIL tier, so editing one of those skills *for any reason* means retrofitting it to the contract first — a one-line fix to `gitea-prs` cannot be committed until that skill complies. This is deliberate, and the retrofit is tracked as Gitea issue #99. Check where a skill stands before starting: `pre-commit run skill-size-check --all-files`.
 - **A second gate ships hot alongside it, and `skill-size-check` will not warn you about it.** `Kyberforge.CompositionNote` — the ADR-0020 Vale rule banning composition and architecture prose from a description — currently fires **10 errors across four skills**: `gitea-issues`, `gitea-labels-milestones`, `gitea-prs` and `gitea-workflow`. Every Vale rule here is `level: error` with no ignorable tier, so touching any of those four means fixing its prose findings as well as its size findings. Scoping a retrofit off `skill-size-check` output alone will leave you blocked at the second gate. Check both: `pre-commit run --all-files`.
 - Install the `vale` binary — required by the `vale-audit-prefilter-skill`/`-agent` pre-commit hooks. Their `files:` patterns are `.apm/`-scoped: `^plugins/[^/]+/\.apm/skills/[^/]+/SKILL\.md$` and `^plugins/[^/]+/\.apm/agents/[^/]+\.agent\.md$`. Only the authoring source triggers them — a `SKILL.md` in the generated mirror matches neither pattern, so prose findings surface only when you edit the file you are supposed to be editing. Without the binary the hooks fail with a bare "command not found" and no install pointer. `brew install vale` (macOS), `snap install vale` (Linux), `choco install vale` (Windows), or see https://vale.sh/docs/vale-cli/installation/. No `vale sync` needed — the `Kyberforge` styles are committed under `plugins/kyberforge/.apm/skills/{skill-audit,agent-audit}/assets/vale/styles/`, not downloaded packages (see ADR-0014).

docs/adr/0020-skill-description-and-body-context-contract.md

@@ -107,8 +107,12 @@ clause**, and a **boundary clause**. Capability enumeration, output-format detai
   up. When an authoring root is found the universe is every skill and agent under
   `<root>/plugins/*/`, plus the target's own apm package and the packages that package declares in
   its own `apm.yml` `dependencies.apm`. Sibling plugins resolve against each other, which is what a
-  monorepo means. Deployed `.claude/`/`.agents/` trees are consulted **only** when no authoring root
+  monorepo means. Deployed `.claude/`/`.agents/` trees are consulted **only** when the walk found no
-  exists — the consumer case, where there is no monorepo to read. What the resolver must never do is
+  plugin monorepo root — whether it landed on a bare `.git` ancestor or on nothing at all. That is
+  the consumer case, where there is no monorepo to read. The condition is which of the two passes
+  matched, never a name-count delta: a single-plugin monorepo re-collects its own package and adds
+  no new name, so a delta test reads zero there and would pull the deployed trees back in. What the
+  resolver must never do is
   derive the universe from its own location: a `${BASH_SOURCE}`-relative repo root leaked this repo's
   39-skill universe into every consumer repo running the hook through pre-commit, so a consumer skill
   routing to `skill-audit` resolved against a plugin it had never installed. Checked