Skill-Namensfamilien: weekly-review -> gtd-weekly-review, dritte Person in allen Descriptions (#129)

Files changed:
- AGENTS.md
- CHANGES.md
- INSTALL.md
- README.md
- VERSION
- instructions/CONTRACT.md
- instructions/dev/stack-close/SKILL.md
- instructions/dev/stack-dev/SKILL.md
- instructions/gtd-weekly-review/SKILL.md
- instructions/setup-instance.md
- instructions/weekly-review/SKILL.md
- instructions/wiki-ingest/SKILL.md
- instructions/wiki-lint/SKILL.md
- instructions/wiki-manage/SKILL.md
- instructions/wiki-query/SKILL.md
- instructions/wiki-status/SKILL.md
- tools/chemenu/tests/test_instructions_cmd.py

instructions/CONTRACT.md

@@ -18,6 +18,8 @@ alongside [AGENTS.md](../AGENTS.md).
 - [Publishing](#publishing)
 - [Writing an instruction](#writing-an-instruction)
   - [A skill's H1 is a name, not an imperative](#a-skills-h1-is-a-name-not-an-imperative)
+  - [A skill's `description` speaks in third person](#a-skills-description-speaks-in-third-person)
+  - [A skill's name declares its family](#a-skills-name-declares-its-family)
   - [A skill's outbound reference is a plain path, not a link](#a-skills-outbound-reference-is-a-plain-path-not-a-link)
   - [Reference depth: bundled files, not repo-wide contracts](#reference-depth-bundled-files-not-repo-wide-contracts)
   - [When a skill carries a copy-in checklist](#when-a-skill-carries-a-copy-in-checklist)
@@ -202,6 +204,38 @@ exception in the same breath - "for promoted skills, the skill name is the title
 That is the whole exception. Everything else in this section binds a `SKILL.md` exactly as it
 binds an instruction.
 
+### A skill's `description` speaks in third person
+
+Anthropic's skill-authoring guidance requires third person in a skill's `description`, because it
+is injected into the system prompt for skill selection and an inconsistent point of view degrades
+that selection - "Processes Excel files and generates reports", never "I can help you process..."
+or "Process...". This binds every `instructions/<name>/SKILL.md` in this repo. The flat
+`instructions/<name>.md` form's `description` (above) is read on demand rather than injected as
+system-prompt metadata, so it keeps the imperative/label freedom that form already allows.
+
+Nothing checks this mechanically - `tools/wikitool docs verify`/`instructions verify` validate a
+`description`'s presence and length, not its grammatical voice - so it holds only as long as each
+new skill is written to match the ones around it.
+
+### A skill's name declares its family
+
+Three prefixes exist today, each naming the subject domain a skill operates on, not the
+distribution boundary it ships behind: `wiki-` for the knowledge pipeline (`wiki-ingest`,
+`wiki-lint`, `wiki-manage`, `wiki-query`, `wiki-status`), `gtd-` for the commitment layer
+(`gtd-weekly-review` - see `kb/gtd/COLLECTION.md` and `docs/knowledge-and-commitment.md` for why
+that layer is named GTD rather than folded into `wiki-`), and `stack-` for the stack's own
+development, nested under `instructions/dev/` and therefore never present in a distributed
+instance (`instructions/dev/` above).
+<!-- dist:strip-start -->
+Dev-instance-only: the two skills in that family today are `stack-dev` and `stack-close`.
+<!-- dist:strip-end -->
+A new skill takes the prefix of the family it belongs to, or opens a new one deliberately - never
+a bare name.
+
+This is a convention, not something the tool enforces: an unprefixed or fourth-family name would
+compile, publish and pass every check exactly like the three above, so it is written down here for
+the next session to read before adding one.
+
 ### A skill's outbound reference is a plain path, not a link
 
 `tools/wikitool instructions sync` copies each `SKILL.md` byte for byte into