develop-web-game

develop-web-game is a skill for Codex from netease-youdao/LobsterAI. It costs 64 tokens per session (2,113 once invoked), scanned A, original, MIT.

A development and testing workflow for browser games built with HTML and JavaScript. It uses automated browser actions, pauses, screenshots, readable game state, and console-error checks to verify each change.

In plain words
What is it for?
Adding or changing one game feature at a time, running repeatable Playwright tests, checking visual output, and inspecting the game's state and errors.
Why use it?
It helps catch broken game behavior and flaky tests while the game is being built, instead of relying only on manual play.

Skill for Codex

Written for Codex: agents/openai.yaml present. Also seen: mentions Codex.

Good fit Adding or changing one game feature at a time, running repeatable Playwright tests, checking visual output, and inspecting the game's state and errors.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/netease-youdao/lobsterai/develop-web-game
About the project

LobsterAI is an open-source desktop AI agent that operates files, commands, browsers, documents, spreadsheets, slides, messaging channels, and scheduled jobs in a user's working environment. It supports office work, research, and custom multi-agent workflows, while catalogue add-ons extend the agent with additional skills and workflows.

netease-youdao/LobsterAI · 5,999 stars · on GitHub · lobsterai.youdao.com

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.

Any agent
npx skills add netease-youdao/LobsterAI --skill develop-web-game
Clone the repo
git clone --depth 1 https://github.com/netease-youdao/LobsterAI

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 develop-web-game

README.md
[![agentmods](https://agentmods.dev/badge/skills/netease-youdao/lobsterai/develop-web-game/github.svg)](https://agentmods.dev/skills/netease-youdao/lobsterai/develop-web-game)
Your own site
<a href="https://agentmods.dev/skills/netease-youdao/lobsterai/develop-web-game"><img src="https://agentmods.dev/badge/skills/netease-youdao/lobsterai/develop-web-game/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for develop-web-game

Your own site · 80×15
<a href="https://agentmods.dev/skills/netease-youdao/lobsterai/develop-web-game"><img src="https://agentmods.dev/badge/skills/netease-youdao/lobsterai/develop-web-game.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 64 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 2,113 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 1 finding, up to medium

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • medium Memory Poisoning · line 127
    Skill attempts to fill the context window with filler content, displacing legitimate instructions and safety constraints. This can degrade agent performance or bypass safety boundaries.
    Fix: Implement context-window management that detects and rejects padding or stuffing attempts. Prioritize system instructions over user-injected content.
How audits are shown
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 5.1 $0.00064 $0.02113
Opus 5 $0.00032 $0.01056
Sonnet 5 $0.00013 $0.00423
Haiku 4.5 $0.00006 $0.00211

Measured 9d ago against content hash 29b745be7676, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

develop-web-game 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 9d ago.

The scan reads SKILL.md. This mod also ships 1 executable file (scripts/web_game_playwright_client.js), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

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

Copies of this mod

3 near-identical copies found in the catalogue:

SKILLs/develop-web-game/SKILL.md · 151 lines

How it starts

The opening of the file, as written. The whole thing — 151 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Develop Web Game

Build games in small steps and validate every change. Treat each iteration as: implement → act → pause → observe → adjust.

Skill paths (set once)

export SKILLS_ROOT="${LOBSTERAI_SKILLS_ROOT:-${SKILLS_ROOT:-$HOME/Library/Application Support/LobsterAI/SKILLs}}"
export WEB_GAME_CLIENT="$SKILLS_ROOT/develop-web-game/scripts/web_game_playwright_client.js"
export WEB_GAME_ACTIONS="$SKILLS_ROOT/develop-web-game/references/action_payloads.json"

Installed skills resolve from $LOBSTERAI_SKILLS_ROOT / $SKILLS_ROOT (production default: app userData/SKILLs, macOS usually ~/Library/Application Support/LobsterAI/SKILLs).

Workflow

  1. Pick a goal. Define a single feature or behavior to implement.
  2. Implement small. Make the smallest change that moves the game forward.
  3. Ensure integration points. Provide a single canvas and window.render_game_to_text so the test loop can read state.
  4. Add window.advanceTime(ms). Strongly prefer a deterministic step hook so the Playwright script can advance frames reliably; without it, automated tests can be flaky.
  5. Initialize progress.md. If progress.md exists, read it first and confirm the original user prompt is recorded at the top (prefix with Original prompt:). Also note any TODOs and suggestions left by the previous agent. If missing, create it and write Original prompt: <prompt> at the top before appending updates.
  6. Verify Playwright availability. Ensure playwright is available (local dependency or global install). If unsure, check npx first.
  7. Run the Playwright test script. You must run $WEB_GAME_CLIENT after each meaningful change; do not invent a new client unless required.
  8. Use the payload reference. Base actions on $WEB_GAME_ACTIONS to avoid guessing keys.
  9. Inspect state. Capture screenshots and text state after each burst.
  10. Inspect screenshots. Open the latest screenshot, verify expected visuals, fix any issues, and rerun the script. Repeat until correct.
  11. Verify controls and state (multi-step focus). Exhaustively exercise all important interactions. For each, think through the full multi-step sequence it implies (cause → intermediate states → outcome) and verify the entire chain works end-to-end. Confirm render_game_to_text reflects the same state shown on screen. If anything is off, fix and rerun. Examples of important interactions: move, jump, shoot/attack, interact/use, select/confirm/cancel in menus, pause/resume, restart, and any special abilities or puzzle actions defined by the request. Multi-step examples: shooting an enemy should reduce its health; when health reaches 0 it should disappear and update the score; collecting a key should unlock a door and allow level progression.
  12. Check errors. Review console errors and fix the first new issue before continuing.
  13. Reset between scenarios. Avoid cross-test state when validating distinct features.
  14. Iterate with small deltas. Change one variable at a time (frames, inputs, timing, positions), then repeat steps 7–13 until stable.

Read the full file on GitHub · 151 lines

Files

What ships with it

6 files 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. 9d ago First seen · 151 lines · 64 tokens per session scan A 29b745be7676

Subscribe to this mod's changes

develop-web-game is a skill published in the GitHub repository netease-youdao/LobsterAI (5,999 stars, last pushed today), licensed MIT. It adds 64 tokens to every session and 2,113 once invoked, about $0.0003 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 2026-08-30.