Visualize
openclaw/openclaw
Create inline visuals for code and explanations, or author persistent OpenClaw dashboard widgets with showwidget.
Cross-cutting Metal pitfalls in NullPlayer's visualization code — command encoder ordering, render-to-texture y-flip, shader availability checks, and the AudioEngine spectrum coalescing pattern that…
Custom licenceAuto-check passed
Install Metal Gotchas
$ npx skills add ad-repo/nullplayer --skill metal-gotchas -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install ad-repo/nullplayer metal-gotchas --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/ad-repo/nullplayer.git skills-src && mkdir -p .claude/skills && cp -r skills-src/skills/metal-gotchas .claude/skills/metal-gotchas && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "metal-gotchas" agent skill from https://github.com/ad-repo/nullplayer/tree/main/skills/metal-gotchas into .claude/skills/metal-gotchas/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "metal-gotchas", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/ad-repo/nullplayer/tree/main/skills/metal-gotchasType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add ad-repo/nullplayer --skill metal-gotchas -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install ad-repo/nullplayer metal-gotchas --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/ad-repo/nullplayer.git skills-src && mkdir -p .agents/skills && cp -r skills-src/skills/metal-gotchas .agents/skills/metal-gotchas && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "metal-gotchas" agent skill from https://github.com/ad-repo/nullplayer/tree/main/skills/metal-gotchas into .agents/skills/metal-gotchas/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "metal-gotchas", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add ad-repo/nullplayer --skill metal-gotchas -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install ad-repo/nullplayer metal-gotchas --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/ad-repo/nullplayer.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/skills/metal-gotchas .cursor/skills/metal-gotchas && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "metal-gotchas" agent skill from https://github.com/ad-repo/nullplayer/tree/main/skills/metal-gotchas into .cursor/skills/metal-gotchas/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "metal-gotchas", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/ad-repo/nullplayer.git --path skills/metal-gotchas--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add ad-repo/nullplayer --skill metal-gotchas -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install ad-repo/nullplayer metal-gotchas --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/ad-repo/nullplayer.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/skills/metal-gotchas .gemini/skills/metal-gotchas && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "metal-gotchas" agent skill from https://github.com/ad-repo/nullplayer/tree/main/skills/metal-gotchas into .gemini/skills/metal-gotchas/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "metal-gotchas", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install ad-repo/nullplayer metal-gotchasInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add ad-repo/nullplayer --skill metal-gotchas -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/ad-repo/nullplayer.git skills-src && mkdir -p .github/skills && cp -r skills-src/skills/metal-gotchas .github/skills/metal-gotchas && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "metal-gotchas" agent skill from https://github.com/ad-repo/nullplayer/tree/main/skills/metal-gotchas into .github/skills/metal-gotchas/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "metal-gotchas", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add ad-repo/nullplayer --skill metal-gotchas -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install ad-repo/nullplayer metal-gotchas --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/ad-repo/nullplayer.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/skills/metal-gotchas .opencode/skills/metal-gotchas && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "metal-gotchas" agent skill from https://github.com/ad-repo/nullplayer/tree/main/skills/metal-gotchas into .opencode/skills/metal-gotchas/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "metal-gotchas", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
Facts
- Skill name
metal-gotchas- GitHub stars
- 158
- Token cost
- ~1.4k tokens
- SKILL.md length
- 588 words
- Files
- 1
- Skills in repo
- 40
- Repo updated
- First seen
- Licence
- Custom licence
At a glance
Cross-cutting Metal pitfalls in NullPlayer's visualization code — command encoder ordering, render-to-texture y-flip, shader availability checks, and the AudioEngine spectrum coalescing pattern that…
- Writing Metal pipelines
- SKILL.md covers Metal Command Encoders — guard…, Wrap CVDisplayLink render…, Metal Render-to-Texture UV… and Spectrum Shader Availability, plus 2 more sections
- Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md
- Chasing visualizer jitter/crash bugs
What it does
Metal Gotchas is an agent skill from ad-repo/nullplayer. Cross-cutting Metal pitfalls in NullPlayer's visualization code — command encoder ordering, render-to-texture y-flip, shader availability checks, and the AudioEngine spectrum coalescing pattern that fixes Classic/Spectrum bar stuttering. Use when writing Metal pipelines or chasing visualizer jitter/crash bugs.
Its SKILL.md is about 1.4k tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.
The repository describes itself as: nullPlayer is a free open source macOS media player with some unique features.
When your agent uses it
- Writing Metal pipelines
- Chasing visualizer jitter/crash bugs
Example prompts
- “/metal-gotchas”
What it can do on your machine
Read from SKILL.md and the folder at commit bd7ddac. It shows what the files ask for, not the result of running them.
Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
No scripts in the folder and no shell commands in SKILL.md (its code samples are swift and metal).
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Context cost
Metal Gotchas loads about 1.4k tokens when it runs. Until then it costs about 81 tokens; SKILL.md has 588 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
Safety
Auto-check passed
The automated check found no risky patterns in SKILL.md.
Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.
SKILL.md
Its licence (Custom licence) doesn't allow us to republish the file, so here is its outline and opening line. It has 588 words (~1,366 tokens).
“Cross-cutting Metal pitfalls that have bitten the visualization stack. Mode-specific shader details live in gpu-vis-modes.”
- name
- metal-gotchas
Files
Just SKILL.md in skills/metal-gotchas of ad-repo/nullplayer.
Open the folder on GitHubat commit bd7ddac
Compare with similar skills
Metal Gotchas next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Metal Gotchas this skillad-repo/nullplayer | 158 | — | ~1.4k | Automated safety check: Pass | Custom licence | |
| Visualizeopenclaw/openclaw | 392k | — | ~2.4k | Automated safety check: Pass | MIT | |
| Visual Stylecalesthio/OpenMontage | 66k | — | ~1.5k | Automated safety check: Pass | AGPL-3.0 | |
| D3 Visualizationnexu-io/open-design | 100k | — | ~523 | Automated safety check: Pass | Apache-2.0 | |
| Visual Regressionthedaviddias/Front-End-Checklist | 74k | — | ~493 | Automated safety check: Pass | MIT | |
| Visualizezai-org/ZCode | 7.7k | — | ~8.7k | Automated safety check: Pass | Custom licence |
Similar skills
Visual Style
calesthio/OpenMontage
Create, extract, and apply portable visual design systems via visual-style.md files.
D3 Visualization
nexu-io/open-design
Teaches the agent to produce D3 charts and interactive data visualizations.
Visual Regression
thedaviddias/Front-End-Checklist
A skill your agent uses when reviewing CI coverage, automated checks, or test strategy related to Use visual regression testing.
Visualize
zai-org/ZCode
Create visualizations and interactive tools directly in conversation.
Visualize
code-yeongyu/oh-my-openagent
Builds a self-contained HTML page (chart, table, diagram, dashboard) to show inline in a thread.
More from ad-repo/nullplayer
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Capture one centred main-window screenshot per skin across every skin system (Classic, Original, Original-Metal, Modern/.wal, Media Player/.wmz, Audion Faces) and assemble them into a fixed-duration…
Vis Classic Guide
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Comprehensive implementation and profile reference for NullPlayer's visclassic mode (CVisClassicCore, VisClassicBridge, SpectrumAnalyzerView integration, menu/keyboard controls…
App Control
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Launch, configure, drive, screenshot and measure the running NullPlayer app.
Chromecast Casting
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Google Cast Protocol v2, message framing, debugging, and test scripts.
Emby Integration
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Emby API, authentication flow, rating scale, streaming, scrobbling, and video playback.
Live UI Testing
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How to debug a defect that only exists on screen — instrument first, drive the app yourself, and measure what is actually drawn.
Questions about Metal Gotchas
What does Metal Gotchas do?
Cross-cutting Metal pitfalls in NullPlayer's visualization code — command encoder ordering, render-to-texture y-flip, shader availability checks, and the AudioEngine spectrum coalescing pattern that…. Metal Gotchas is an agent skill from ad-repo/nullplayer. Cross-cutting Metal pitfalls in NullPlayer's visualization code — command encoder ordering, render-to-texture y-flip, shader availability checks, and the AudioEngine spectrum coalescing pattern that fixes Classic/Spectrum bar stuttering.
When should I use Metal Gotchas?
Metal Gotchas fits situations like: writing Metal pipelines; chasing visualizer jitter/crash bugs.
How do I install Metal Gotchas in Claude Code?
Run `npx skills add ad-repo/nullplayer --skill metal-gotchas -a claude-code`. Or copy the skill folder (skills/metal-gotchas in ad-repo/nullplayer) into .claude/skills/metal-gotchas in your project. Claude Code loads it when a task matches its description.
How do I install Metal Gotchas in Codex?
Run `npx skills add ad-repo/nullplayer --skill metal-gotchas -a codex`. Or copy the skill folder (skills/metal-gotchas in ad-repo/nullplayer) into .agents/skills/metal-gotchas in your project. Codex loads it when a task matches its description.
Can I use Metal Gotchas in Cursor, Gemini CLI or GitHub Copilot?
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add ad-repo/nullplayer --skill metal-gotchas -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/metal-gotchas, .gemini/skills/metal-gotchas, .github/skills/metal-gotchas and .opencode/skills/metal-gotchas in your project.
What does Metal Gotchas need to run?
SKILL.md names no scripts, command-line tools or credentials: Metal Gotchas is instructions for the agent only.
Does Metal Gotchas access the network?
SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.
Is Metal Gotchas safe to install?
Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.
What licence does Metal Gotchas use?
Metal Gotchas has a licence file (the repository's licence) that doesn't match a standard licence. Read it on GitHub before reusing the skill.
How many tokens does Metal Gotchas use?
About 1.4k tokens (SKILL.md is roughly 5.5k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.
What are the alternatives to Metal Gotchas?
Skills that share tags, products or a category with Metal Gotchas: Visualize (openclaw/openclaw, 392k stars), Visual Style (calesthio/OpenMontage, 66k stars), D3 Visualization (nexu-io/open-design, 100k stars) and Visual Regression (thedaviddias/Front-End-Checklist, 74k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Metal Gotchas?
ad-repo (a GitHub user) maintains it in ad-repo/nullplayer, which has 158 GitHub stars. The repository holds 40 skills in this directory. The repository was last updated on October 11, 2026.
Source: ad-repo/nullplayer on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.