build-game-inventory

build-game-inventory is a skill for Codex from devinilabs/pro-skill. It costs 54 tokens per session (313 once invoked), scanned A, a copy of build-game-inventory, MIT.

A skill for building or repairing game inventory systems, including items, loot, equipment, tooltips, drag-and-drop, saving, and progression. It treats item data as one typed, serializable source of truth.

In plain words
What is it for?
Use it when implementing item schemas, pickup and equipment flows, stack limits, inventory persistence, save migration, drag-and-drop behavior, tooltips, or regression tests for inventory changes.
Why use it?
It helps prevent lost or duplicated items by requiring transfers such as pickup, equip, swap, and selling to be validated and committed as one operation. It also covers accessible interaction and tests for save/load and failure cases.

Skill for Codex

Written for Codex: agents/openai.yaml present.

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 skills/devinilabs/pro-skill/build-game-inventory
Any agent
npx skills add devinilabs/pro-skill --skill build-game-inventory
Clone the repo
git clone --depth 1 https://github.com/devinilabs/pro-skill

Made for: Codex.

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 build-game-inventory

README.md
[![agentmods](https://agentmods.dev/badge/skills/devinilabs/pro-skill/build-game-inventory.svg)](https://agentmods.dev/skills/devinilabs/pro-skill/build-game-inventory)
Your own site
<a href="https://agentmods.dev/skills/devinilabs/pro-skill/build-game-inventory"><img src="https://agentmods.dev/badge/skills/devinilabs/pro-skill/build-game-inventory.svg" alt="Measured on agentmods" height="20"></a>
Per session 54 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 313 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 100% copy Near-identical to another mod 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 5.1 $0.00054 $0.00313
Opus 5 $0.00027 $0.00156
Sonnet 5 $0.00011 $0.00063
Haiku 4.5 $0.00005 $0.00031

Measured 6d ago against content hash 361fed9d4641, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

build-game-inventory 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 6d 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.

Origin

This is a copy

100% identical to build-game-inventory — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

agent-skills/game-development/build-game-inventory/SKILL.md · 32 lines

What it actually says

Build Game Inventory

Use one typed, serializable item source of truth and make every transfer atomic.

Define the item contract

Model stable IDs, item definitions, ownership, stack limits, equipment compatibility, effects, rarity, presentation data, and migration version separately. Runtime UI must reference definitions by ID rather than duplicate stats or descriptions.

Implement transfers as transactions

For pickup, equip, unequip, swap, drag/drop, consume, and sell:

  1. Validate source ownership and destination legality.
  2. Compute the entire next inventory/equipment state.
  3. Commit once or reject without changing either side.
  4. Persist only after the committed state is valid.

Never remove an item before confirming a legal destination. Preserve item identity across a swap and prevent duplicate effect registration.

Build usable UI

Expose slot compatibility, equipped state, quantity, tooltip facts, and failure feedback. Support keyboard and touch alternatives to drag-only interactions. Keep focus behavior, dialogs, and tooltips accessible.

Test loss boundaries

Cover invalid destinations, full inventory, duplicate pickup, equip swap, mid-action swap, save/load, schema migration, reset/new game, tooltip updates, and repeated dispatch. Validate that total owned item identity is conserved except for explicit consumption or reward rules.

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. 6d ago First seen · 32 lines · 54 tokens per session scan A 361fed9d4641

Subscribe to this mod's changes

build-game-inventory is a skill published in the GitHub repository devinilabs/pro-skill (23 stars, last pushed 23d ago), licensed MIT. It adds 54 tokens to every session and 313 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to build-game-inventory, differing in 0 lines, and is treated as a copy.