| name | asset-spec |
| description | "Generate per-asset visual specifications and AI generation prompts from GDDs, level docs, or character profiles. Produces structured spec files and updates the master asset manifest. Run after art bible and GDD/level design are approved, before production begins." |
| argument-hint | "[system:<name> | level:<name> | character:<name>] [--review full|lean|solo]" |
| user-invocable | true |
| allowed-tools | Read, Glob, Grep, Write, Edit, Task, AskUserQuestion |
If no argument is provided, check whether design/assets/asset-manifest.md exists:
- If it exists: read it, find the first context (system/level/character) with any asset at status "Needed" but no spec file written yet, and use
AskUserQuestion:
- Prompt: "The next unspecced context is [target]. Generate asset specs for it?"
- Options:
[A] Yes — spec [target] / [B] Pick a different target / [C] Stop here
- If no manifest: fail with:
"Usage: /asset-spec system:<name> — e.g., /asset-spec system:tower-defense
Or: /asset-spec level:iron-gate-fortress / /asset-spec character:frost-warden
Run after your art bible and GDDs are approved."
Phase 0: Parse Arguments
Extract:
- Target type:
system, level, or character
- Target name: the name after the colon (normalize to kebab-case)
- Review mode:
--review [full|lean|solo] if present
Mode behavior:
full (default): spawn both art-director and technical-artist in parallellean: spawn art-director only — faster, skips technical constraint passsolo: no agent spawning — main session writes specs from art bible rules alone. Use for simple asset categories or when speed matters more than depth.
Phase 1: Gather Context
Read all source material before asking the user anything.
Required reads:
Source doc reads (by target type):
- system: Read
design/gdd/[target-name].md. Extract the Visual/Audio Requirements section. If it doesn't exist or reads [To be designed]:
"The Visual/Audio section of design/gdd/[target-name].md is empty. Either run /design-system [target-name] to complete the GDD, or describe the visual needs manually."
Use AskUserQuestion: [A] Describe needs manually / [B] Stop — complete the GDD first
- level: Read
design/levels/[target-name].md. Extract art requirements, asset list, VFX needs, and the art-director's production concept specs from Step 4.
- character: Read
design/narrative/characters/[target-name].md or search design/narrative/ for the character profile. Extract visual description, role, and any specified distinguishing features.
Optional reads:
- Existing manifest: Read
design/assets/asset-manifest.md if it exists — extract already-specced assets for this target to avoid duplicates.
- Related specs: Glob
design/assets/specs/*.md — scan for assets that could be shared (e.g., a common UI element specced for one system might apply here too).
Present context summary:
Asset Spec: [Target Type] — [Target Name]
- Source doc: [path] — [N] asset types identified
- Art bible: found — Asset Standards at Section 8
- Existing specs for this target: [N already specced / none]
- Shared assets found in other specs: [list or "none"]
Phase 2: Asset Identification
From the source doc, extract every asset type mentioned — explicit and implied.
For systems: look for VFX events, sprite references, UI elements, audio triggers, particle effects, icon needs, and any "visual feedback" language.
For levels: look for unique environment props, atmospheric VFX, lighting setups, ambient audio, skybox/background, and any area-specific materials.
For characters: look for sprite sheets (idle, walk, attack, death), portrait/avatar, VFX attached to abilities, UI representation (icon, health bar skin).
Group assets into categories:
- Sprite / 2D Art — character sprites, UI icons, tile sheets
- VFX / Particles — hit effects, ambient particles, screen effects
- Environment — props, tiles, backgrounds, skyboxes
- UI — HUD elements, menu art, fonts (if custom)
- Audio — SFX, music tracks, ambient loops (note: audio specs are descriptions only — no generation prompts)
- 3D Assets — meshes, materials (if applicable per engine)
Present the full identified list to the user. Use AskUserQuestion:
- Prompt: "I identified [N] assets across [N] categories for [target]. Review before speccing:"
- Show the grouped list in conversation text first
- Options:
[A] Proceed — spec all of these / [B] Remove some assets / [C] Add assets I didn't catch / [D] Adjust categories
Do NOT proceed to Phase 3 without user confirmation of the asset list.
Phase 3: Spec Generation
Spawn specialist agents based on review mode. Issue all Task calls simultaneously — do not wait for one before starting the next.
Full mode — spawn in parallel:
art-director via Task:
- Provide: full asset list from Phase 2, art bible Visual Identity Statement, Color System, Shape Language, the source doc's visual requirements, and any reference games/art mentioned in the art bible Section 9
- Ask: "For each asset in this list, produce: (1) a 2–3 sentence visual description anchored to the art bible's shape language and color system — be specific enough that two different artists would produce consistent results; (2) a generation prompt ready for use with AI image tools (Midjourney/Stable Diffusion style — include style keywords, composition, color palette anchors, negative prompts); (3) which art bible rules directly govern this asset (cite by section). For audio assets, describe the sonic character instead of a generation prompt."
technical-artist via Task:
- Provide: full asset list, art bible Asset Standards (Section 8), technical-preferences.md performance budgets, engine name and version
- Ask: "For each asset in this list, specify: (1) exact dimensions or polycount (match the art bible Asset Standards tiers — do not invent new sizes); (2) file format and export settings; (3) naming convention (from technical-preferences.md); (4) any engine-specific constraints this asset type must respect; (5) LOD requirements if applicable. Flag any asset type where the art bible's preferred standard conflicts with the engine's constraints."
Lean mode — spawn art-director only (skip technical-artist).
Solo mode — skip both. Derive specs from art bible rules alone, noting that technical constraints were not validated.
Collect both responses before Phase 4. If any conflict exists between art-director and technical-artist (e.g., art-director specifies 4K textures but technical-artist flags the engine budget requires 512px), surface it explicitly — do NOT silently resolve.
Phase 4: Compile and Review
Combine the agent outputs into a draft spec per asset. Present all specs in conversation text using this format:
## ASSET-[NNN] — [Asset Name]
| Field | Value |
|-------|-------|
| Category | [Sprite / VFX / Environment / UI / Audio / 3D] |
| Dimensions | [e.g. 256×256px, 4-frame sprite sheet] |
| Format | [PNG / SVG / WAV / etc.] |
| Naming | [e.g. vfx_frost_hit_01.png] |
| Polycount | [if 3D — e.g. <800 tris] |
| Texture Res | [e.g. 512px — matches Art Bible §8 Tier 2] |
**Visual Description:**
[2–3 sentences. Specific enough for two artists to produce consistent results.]
**Art Bible Anchors:**
- §3 Shape Language: [relevant rule applied]
- §4 Color System: [color role — e.g. "uses Threat Blue per semantic color rules"]
**Generation Prompt:**
[Ready-to-use prompt. Include: style keywords, composition notes, color palette anchors, lighting direction, negative prompts.]
**Status:** Needed
After presenting all specs, use AskUserQuestion:
- Prompt: "Asset specs for [target] — [N] assets. Review complete?"
- Options:
[A] Approve all — write to file / [B] Revise a specific asset / [C] Regenerate with different direction
If [B]: ask which asset and what to change. Revise inline and re-present. Do NOT re-spawn agents for minor text revisions — only re-spawn if the visual direction itself needs to change.
If [C]: ask what direction to change. Re-spawn the relevant agent with the updated brief.
Phase 5: Write Spec File
After approval, ask: "May I write the spec to design/assets/specs/[target-name]-assets.md?"
Write the file with:
# Asset Specs — [Target Type]: [Target Name]
> **Source**: [path to source GDD/level/character doc]
> **Art Bible**: design/art/art-bible.md
> **Generated**: [date]
> **Status**: [N] assets specced / [N] approved / [N] in production / [N] done
[all asset specs in ASSET-NNN format]
Then update design/assets/asset-manifest.md. If it doesn't exist, create it:
# Asset Manifest
> Last updated: [date]
## Progress Summary
| Total | Needed | In Progress | Done | Approved |
|-------|--------|-------------|------|----------|
| [N] | [N] | [N] | [N] | [N] |
## Assets by Context
### [Target Type]: [Target Name]
| Asset ID | Name | Category | Status | Spec File |
|----------|------|----------|--------|-----------|
| ASSET-001 | [name] | [category] | Needed | design/assets/specs/[target]-assets.md |
If the manifest already exists, append the new context block and update the Progress Summary counts.
Ask: "May I update design/assets/asset-manifest.md?"
Phase 6: Close
Use AskUserQuestion:
- Prompt: "Asset specs complete for [target]. What's next?"
- Options:
[A] Spec another system — /asset-spec system:[next-system][B] Spec a level — /asset-spec level:[level-name][C] Spec a character — /asset-spec character:[character-name][D] Run /asset-audit — validate delivered assets against specs[E] Stop here
Asset ID Assignment
Asset IDs are assigned sequentially across the entire project — not per-context. Read the manifest before assigning IDs to find the current highest number:
Grep pattern="ASSET-" path="design/assets/asset-manifest.md"
Start new assets from ASSET-[highest + 1]. This ensures IDs are stable and unique across the whole project.
If no manifest exists yet, start from ASSET-001.
Shared Asset Protocol
Before speccing an asset, check if an equivalent already exists in another context's spec:
- Common UI elements (health bars, score displays) are often shared across systems
- Generic environment props may appear in multiple levels
- Character VFX (hit sparks, death effects) may reuse a base spec with color variants
If a match is found: reference the existing ASSET-ID rather than creating a duplicate. Note the shared usage in the manifest's referenced-by column.
"ASSET-012 (Generic Hit Spark) already specced for Combat system. Reusing for Tower Defense — adding tower-defense to referenced-by."
Error Recovery Protocol
If any spawned agent returns BLOCKED or cannot complete:
- Surface immediately: "[AgentName]: BLOCKED — [reason]"
- In
lean mode or if technical-artist blocks: proceed with art-director output only — note that technical constraints were not validated
- In
solo mode or if art-director blocks: derive descriptions from art bible rules — flag as "Art director not consulted — verify against art bible before production"
- Always produce a partial spec — never discard work because one agent blocked
Collaborative Protocol
Every phase follows: Identify → Confirm → Generate → Review → Approve → Write
- Never spec assets without first confirming the asset list with the user
- Always anchor specs to the art bible — a spec that contradicts the art bible is wrong
- Surface all agent disagreements — do not silently pick one
- Write the spec file only after explicit approval
- Update the manifest immediately after writing the spec
Recommended Next Steps
- Run
/asset-spec [next-context] to continue speccing remaining systems, levels, or characters
- Run
/asset-audit to validate delivered assets against the written specs and identify gaps or mismatches
