designer

designer is a command for coding agents from xthenyo/game-mcp. It costs 16 tokens per session (544 once invoked), scanned A, original, MIT.

A command set for writing and organising a game design bible: the project documents that describe its story, world, mechanics, characters, quests, events, art, audio, and release settings.

In plain words
What is it for?
Use it to document the game's vision, rules, systems, entities, relationships, maps, narrative branches, quests, events, visual style, and platform configuration.
Why use it?
It keeps design decisions and terminology in one structured set of documents so the game remains consistent as it grows.

Command

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add commands/xthenyo/game-mcp/designer
Clone the repo
git clone --depth 1 https://github.com/xthenyo/game-mcp

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for designer

README.md
[![agentmods](https://agentmods.dev/badge/commands/xthenyo/game-mcp/designer.svg)](https://agentmods.dev/commands/xthenyo/game-mcp/designer)
Your own site
<a href="https://agentmods.dev/commands/xthenyo/game-mcp/designer"><img src="https://agentmods.dev/badge/commands/xthenyo/game-mcp/designer.svg" alt="Measured on agentmods" height="20"></a>
Per session 16 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 544 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00016 $0.00544
Opus 5 $0.00008 $0.00272
Sonnet 5 $0.00003 $0.00109
Haiku 4.5 $0.00002 $0.00054

Measured 3d ago against content hash d6daa89fa1d1, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

designer scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 3d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

templates/common/claude/commands/designer.md · 57 lines

What it actually says

DESIGNER

Bible documentation: entities, story, world, mechanics, audio, balance.

Activation

  1. get_context("DESIGNER") -> start from next_task field
  2. claim_task(id, "DESIGNER")
  3. Follow agent_prompt exactly
  4. log_decision("DESIGNER", "design decision", tag="ARCH|NAMING")
  5. complete_task(id, "DESIGNER", self_review="what I wrote + is Bible consistent?")
  6. Continue to next OPEN task if available

Research if needed

gemini "[game genre] [topic] design patterns 2026"

Bible Structure

docs/bible/
├── 00-meta/        -> project.yaml, glossary.md
├── 01-vision/      -> gdd.md, pillars.md, references.md
├── 02-mechanics/   -> core-loop, systems, rules, turns, actions, resources
├── 03-entities/    -> player, npcs, groups, archetypes
├── 04-attributes/  -> schema, absolute, bipolar, boolean
├── 05-world/       -> map, territories, locations, buildings
├── 06-narrative/   -> story, branches, decisions
├── 07-quests/      -> main, side, random, timed
├── 08-relations/   -> schema, dynamics, player-npc, npc-npc
├── 09-events/      -> triggers, turn-end, random
├── 10-art/         -> style-guide, ui-specs, visual-pipeline
├── 11-release/     -> platform config, build settings
└── 12-audio/       -> audio-specs

Writing Rules

  • [TBD], [TODO], [PLACEHOLDER] forbidden. Write concretely or don't write at all.
  • IDs: [category]_[name] -> npc_merchant_01, territory_forest
  • Be specific: "5 NPCs: Merchant (power:8), Guard (power:6)" — not "several NPCs"
  • Numerical: "Power: 8/10" — not "powerful"
  • Cross-reference: [filename](file.md)

Don't

  • Write code, generate art
  • Edit files outside Bible
  • Off-task "improvements"
Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 3d ago First seen · 57 lines · 16 tokens per session scan A d6daa89fa1d1

Subscribe to this mod's changes

designer is a command published in the GitHub repository xthenyo/game-mcp (0 stars, last pushed 5mo ago), licensed MIT. It adds 16 tokens to every session and 544 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.