| name | unikit-gd-system |
| description | Author and own ONE system's design document (the A–K SYSTEM GDD) at .unikit/gamedesign/systems/SYS-<slug>.md — the depth layer of the GDD, single-system scope. Create the skeleton and walk the collaborative section-cycle to write its parameters, rules, formulas, and acceptance criteria ("detail the combat system", "write the GDD for the inventory system", "fill in the rest of this system doc", "spec out the parameters of X"), AND revise it after approval under the delta discipline ("raise the damage by 10%", "tune the economy", "rework the status system", "nerf X", "change this rule") — a number change is Tuning, a small rule a Tweak, restructuring a Rework; each bumps the version and logs the delta. To add a NEW system or restructure the system map use /unikit-gd-spec; to edit GAME.md content use /unikit-gd-spec; the moment an edit also touches a second system, a content type, a flow, or GAME.md (two or more zones) use /unikit-gd-apply; to invent a brand-new game concept use /unikit-gd-brainstorm. |
| argument-hint | <system name | SYS-slug> ["<what to change>"] (mode inferred from doc state + intent; no flags) |
| allowed-tools | ["Read","Write","Edit","Glob","Grep","Bash(ls *)","Bash(find *)","Bash(wc *)","Bash(date *)","AskUserQuestion"] |
| disable-model-invocation | false |
| user-invocable | true |
| metadata | {"author":"unikit","version":"1.0","category":"game-design"} |
Game Design — Per-System GDD (Authoring & Revision)
Own one system's design document at
.unikit/gamedesign/systems/SYS-<slug>.md — eleven sections (A–K) plus any
domain section-packs. This skill owns the system zone (gd-principles → Zone
Ownership): the full lifecycle of a SYSTEM.md lives here — create the
skeleton, fill its placeholders, and revise approved content (Tuning /
Tweak / Rework) under the delta discipline. There is no separate editor skill.
It never creates the master spec or the map, and never edits GAME.md content —
that is unikit-gd-spec; player-action flows are unikit-gd-flow's.
Language Awareness — BLOCKING PRE-REQUISITE
BEFORE producing ANY output, silently read .unikit/system/LANGUAGE_RULES.md
and apply it to all output and artifacts (fall back to English if it is missing) —
including the rule to translate concepts, not transliterate jargon.
gd-principles → "Language" adds the game-design specifics: which IDs and stored
field values stay English. Do not announce the language setting.
Phase 0 — Bootstrap
Silently load — do not narrate:
-
.unikit/system/gamedesign/gd-principles.md (the core) — the collaborative
protocol, the facts registry / ID conventions, and the language rules. Plus, from
the same gamedesign/ folder, the shards this skill needs: gd-authoring.md
(the section-cycle authoring contract + the delta discipline — the
mandatory Version +1 → changelog → registry-check → recommend-verify tail),
gd-lifecycle.md (the lifecycle & status spine), and gd-provenance.md
(the import provenance markers). This skill applies that contract; it does not
restate the mechanics. If missing, warn (unikit-ai update) and fall back to the
protocol as summarized in this file.
-
.unikit/gamedesign/GAME.md — pillars, loops, non-goals the system must
serve (its roster is in ## System Map [gen]). If it does not exist, stop —
there is no master spec yet. Read .unikit/gamedesign/concepts/INDEX.md (if it
exists) to route precisely: a drafted/approved concept present → recommend
/unikit-gd-spec (build the master spec from it); no concept — or no
concepts/INDEX.md (or no concepts/ dir) at all → recommend
/unikit-gd-brainstorm first, then /unikit-gd-spec.
-
.unikit/gamedesign/GD-IDS.yaml — find the target system's entry under
systems. If there is no entry, the system is not on the map: offer to add
it via /unikit-gd-spec (add-system — graft this one system onto the map, not
a remap), or pick an existing not-started system. Do not author an off-map
system.
-
.unikit/memory/gamedesign/RULES_INDEX.md — load the core domain
rules for this system's behavioural domain, on demand by Load When, plus
any studio library rule on the same topic. Read the domain from the system's
name and Overview (the behaviour it drives), not from the coarse GD-IDS
category. When the behaviour is unambiguous, attach the matching domain
automatically (its section-pack rides along — auto-attached with a veto, see item 6
and Phase 4); when it is ambiguous or the category is coarse (Gameplay / Meta),
settle it with one plain AskUserQuestion — framed as an outcome, no codes — rather
than guessing. A system may match more than one domain; they combine:
| Domain | Core rules to load | Section-pack |
|---|
| combat / mechanics | balance, frameworks | combat |
| ai-behavior | balance, frameworks | ai-behavior |
| economy / loot | economy, balance | economy |
| progression / unlock | progression, balance | progression |
| level / content | level-design | levels |
| narrative / dialogue | narrative | narrative |
| ui / onboarding | ux-onboarding | ux |
| liveops / events | liveops, economy | liveops |
| persistence | progression | persistence |
| monetization | monetization-ethics, economy | monetization |
| meta / other | frameworks, core-loops | — |
Every system also touches accessibility (section J) — load accessibility
when authoring J. Obey the index's Rule-Loading Discipline: load by Load When,
load a reference only from its parent rule's > **References**:, and never glob the
memory tree (.unikit/memory/gamedesign/**) to discover rules.
-
.unikit/RULES.md (if present) — project overrides, highest priority.
-
{{skills_dir}}/{{self_name}}/references/section-packs.md — the catalog of
domain section-packs. On an unambiguous domain the matching pack is
auto-attached — announced to the user in one outcome-language phrase (what it
adds for the player / the design, never the word "pack" or a code) that they can
veto; on an ambiguous domain a single plain Yes/No decides it. Never a mandatory
pass after section K, never surfaced as registry jargon. Load the pack named in the
table above (when one applies).
-
Schema guard (clean break — no automatic migration). GD-IDS.yaml MUST be
version: 2. If it is still version: 1, STOP and report: the design
workspace is on the pre-v2 layout — v2 dropped the standalone markdown
system-index and now renders the roster into GAME.md (## System Map [gen]);
there is no automatic migration. Tell the user to bump GD-IDS.yaml to
version: 2 and fold the legacy system-index rows into GAME.md's
## System Map [gen] before re-running.
One-way boundary: never read .unikit/code/, project source, or build
artifacts. The only external read is SOURCE.md during an import (Phase 1).
Phase 1 — Context
Gather the facts the system must stay consistent with (read-only):
- Known facts from
GD-IDS.yaml — pillars (implements targets), entities,
formulas, and terms already locked by other systems. These are constraints, not
suggestions.
- Neighbor GDDs — for each system this one depends on (from the GD-IDS
depends_on, rendered in GAME.md ## System Map), read its header and sections
D (Formulas) and F (Dependencies) to match data interfaces.
- Recent
unikit-gd-verify reports for this system, if any
(.unikit/gamedesign/reviews/).
- Import source — if
GD-IDS/GAME mention an import, or a
researches/<date>_import-*/SOURCE.md covers this system, read it: section
content is extracted from it, not regenerated. Mark provenance per
gd-provenance → Provenance: place <!-- provenance: extracted from SOURCE.md -->
under each section lifted from the source and <!-- provenance: generated -->
under each section inferred to complete the skeleton; untagged sections are
normal authored content.
- Explore research (internal design lens) — if this system was grafted from an
unikit-gd-explore brief, discover the research deterministically (survives a
/clear): read the system's GD-IDS research: pointer (authoritative), falling
back to the researches/INDEX.md entry whose Target: is this SYS-<slug>. Read
that research's RESEARCH_BRIEF.md → ## New Feature Plan block and use its
section seeds as the starting drafts — a seeded section is drafted
silently in Generation (Phase 4) and confirmed in the group review (Phase 5); a
seed is a draft, not an approved write. For
a revision (Edit), the matching block is ## Improvement Plan — its
ready-to-apply delta lines (<Section>: <old> → <new>), expected scale, touched
facts, and any RF-<date>-n it closes pre-fill the change set (the user still
approves every edit). These explore-seeded drafts are untagged normal authored
content — do not mark them extracted / generated (those markers are for
imports only; this is the generalization of import-reading stated canonically
in gd-provenance → Provenance, which this skill applies rather than restates).
Phase 2 — Resolve Mode + Depth (no flags)
Check .unikit/gamedesign/systems/SYS-<slug>.md and read the intent in the prompt:
- Does not exist → Create: build the skeleton (Phase 3), then author from
section A.
- Exists and the prompt describes a change to approved content (a value,
rule, or structure: "raise damage", "tune the economy", "rework the status
system", "nerf X", "change this rule") → Edit: classify the scale and apply
the delta (Revision below). Approved text is changed only through this path.
- Exists with
[To be designed] placeholders and the intent is to continue /
fill (or no change is described) → Fill: resume from the remaining placeholders.
Approved text is never overwritten — only placeholders are filled. Skip the
skeleton sub-step (Phase 3.1); still fork-scan and run Phases 4–5 over the
placeholders.
- Exists, complete, no change described → detailing is done; nothing to author.
Offer review / verify (Phase 6) and stop.
If the system name is ambiguous (matches several entries, or none) →
AskUserQuestion listing candidates. Never guess the target.
Depth gate (Create / Fill only). Once the mode is Create or Fill, present one
depth picker — the named tiers core/standard/full, each with what it adds, not bare
letters:
AskUserQuestion: How deep should this pass go?
Options:
1. core (recommended) — the floor that gets the doc to a solid, usable base: Overview,
Player Fantasy, Detailed Design, Formulas, Acceptance Criteria.
2. standard — core + Edge Cases, Dependencies, Tuning Knobs, Telemetry, Accessibility.
3. full — every section + the relevant domain pack(s).
The picked tier is the ephemeral scope of this pass — NOT stored (gd-authoring /
gd-lifecycle); the lasting fact is the inferred status at Phase 6. The matching
section-pack for the system's domain (Phase 0 table) is auto-attached when the
domain is unambiguous — announced in one outcome-language phrase you can veto; an
ambiguous domain gets a single plain Yes/No in the Phase 4 decision round. Edit mode
skips the depth gate entirely (it lies flat on the Revision flow).
Load the Mode Body
With the mode resolved (Phase 2) and the depth picked (Create / Fill only), load the
matching body on demand and follow it — do not keep both bodies in context. Each
returns to Phase 6 (Final) below.
| Mode | Reference body |
|---|
| Create / Fill | {{skills_dir}}/{{self_name}}/references/mode-author.md — the Decision-First section-cycle: the A–K section map + core-set, Phase 3 (Skeleton + Fork-Scan), Phase 4 (Decision Interview + Generation), Phase 5 (Group Review). |
| Edit | {{skills_dir}}/{{self_name}}/references/mode-revise.md — classify the scale (Tuning / Tweak / Rework / Structural-redirect), apply the change, then the mandatory delta tail. |
Phase 6 — Final: Registry & State + Handoff
Registry & State (Create / Fill)
After the sections are authored and accepted:
-
Scan the GDD for registry candidates — entities, formulas, and constants
referenced in two or more places (within this doc or cross-system). Internal
single-use values stay in the GDD.
-
Present a NEW / KNOWN summary and get approval to write GD-IDS.yaml
(entities, formulas, plus the systems entry's doc_status / version).
Existing values are never changed silently; every fact carries its source.
-
Status (inferred — gd-lifecycle). Set the system's status in the two places
that must agree — the SYSTEM.md header > Status: token (inside the combined
header line, not a separate bold line) and the GD-IDS.yaml doc_status:
detailed once the whole core-set (A/B/C/D/H) is authored.
- held at
skeleton while any core section carries <!-- deferred --> (the
soft floor guard; the WARN in Phase 4) — the status does not rise to
detailed.
- when the core is complete but ≥1 non-core section is deferred, the status is
detailed and the ## System Map [gen] renders it detailed · partial (n/m)
(inferred from the markers, never a stored field).
Set version: 1 in GD-IDS.yaml (and the header), write the initial changelog
block to section K (#### v1 — <date> — initial design with the
AC: + AC-<slug>-1 … N (new) line) — the single current block (K1).
The ## System Map [gen] renders this system's status/version (incl. the · partial
suffix) read-only from GD-IDS; it is not this skill's surface — it is owned by
unikit-gd-spec (B1) and re-renders on its next touch. unikit-gd-verify is read-only —
it prints the System Map freshness, it does not re-render it (gd-lifecycle →
Lifecycle & Status). Recommending verify (below) surfaces the staleness.
Handoff
Recommend the next steps (do not auto-invoke):
- ✅ Verify consistency & impact — /unikit-gd-verify SYS-
- 🔍 Qualitative review (fresh session) — /unikit-gd-review systems/SYS-.md
- 🧩 Detail the next system — /unikit-gd-system
A review is most independent in a fresh session (the reviewer should not have
authored the doc). unikit-gd-verify is read-only — it checks the doc against the
registry and prints dependent impact + the ## System Map [gen] freshness (the map
re-renders on the next unikit-gd-spec touch).
Final: Compact Report
The terminal plaque (TIER A — gd-principles → Language): lead with the name; the
SYS- / AC- ids ride along as parenthetical copy-paste tags; render the lifecycle
status as a plain phrase, never the raw enum.
System: <name> (SYS-<slug>)
Mode: <create | fill | edit (tuning|tweak|rework)> · Depth: <core | standard | full> (create/fill)
Doc: .unikit/gamedesign/systems/SYS-<slug>.md — <ready | ready, a couple of optional blocks left | skeleton, main blocks not filled yet>, vN
Sections authored/edited: <the named list> [deferred: <names carrying <!-- deferred --> > | none]
Registry: +<E> entities, +<F> formulas, +<T> terms (GD-IDS.yaml)
Acceptance criteria: AC-<slug>-1 … AC-<slug>-N [AC delta on an edit: +<n> / changed <n> / removed <n>]
No summary document, no report file.
Ownership Boundaries
- Owns: the full lifecycle of
systems/SYS-<slug>.md — creating the
skeleton, filling placeholders, and revising approved content (Tuning / Tweak
/ Rework, with the version bump + changelog; the status stays detailed); the system's
GD-IDS.yaml facts (entities, formulas, terms) and its doc_status /
version.
- Not this skill:
GAME.md content or structure / the system map →
unikit-gd-spec; player-action flows → unikit-gd-flow; quality verdicts →
unikit-gd-review; consistency & impact → unikit-gd-verify (read-only — it prints,
it does not re-render); the ## System Map [gen] render → unikit-gd-spec.
- Never: write, fill, or edit without approval; overwrite approved text outside
the delta discipline; skip the version bump or changelog on an edit (unrecorded
delta); change a
GD-IDS.yaml value silently; delete or renumber an ID; touch
structure or GAME.md; read the code workspace or project source.
Quick Reference
/unikit-gd-system SYS-combat → create skeleton + author A–K (if no doc yet)
/unikit-gd-system combat → resolve to the SYS-slug; same flow
/unikit-gd-system SYS-combat → resume filling placeholders (partial doc)
/unikit-gd-system SYS-combat "raise grunt damage 10%" → Tuning: edit G/C, one approval
/unikit-gd-system combat "small fix to the parry rule" → Tweak: targeted edit
/unikit-gd-system SYS-combat "rework the status system" → Rework: section-cycle old-vs-new