muapi-youtube-thumbnail

muapi-youtube-thumbnail is a skill for OpenCode from SamurAIGPT/Generative-Media-Skills. It costs 30 tokens per session (815 once invoked), scanned B, original, MIT.

A skill for designing a single 16:9 YouTube thumbnail, the preview image viewers see before opening a video.

In plain words
What is it for?
Use it to create thumbnails from a title, with an optional channel style and description of a person or subject to show.
Why use it?
It provides a clear way to plan the subject, short overlay text, contrast, and visual style around a video's topic.

Skill for OpenCode

Written for OpenCode: installed under .opencode/.

not rated 4.3krepo +40 3d ago B scan Socket: passSnyk: passSkillSpector: warn 30 tokens original MIT

Good fit Use it to create thumbnails from a title, with an optional channel style and description of a person or subject to show.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/samuraigpt/generative-media-skills/muapi-youtube-thumbnail
About the project

Generative-Media-Skills is a toolkit that lets AI agents generate, edit, and display images, videos, and audio through the muapi command-line interface. It is for users of Claude Code, Cursor, Gemini CLI, and OpenCode who need multimodal media-generation workflows. The catalogue entries are the skills that expose these media capabilities to coding agents.

SamurAIGPT/Generative-Media-Skills · 4,259 stars · on GitHub · muapi.ai

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 SamurAIGPT/Generative-Media-Skills --skill muapi-youtube-thumbnail
Clone the repo
git clone --depth 1 https://github.com/SamurAIGPT/Generative-Media-Skills

Made for: OpenCode.

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 muapi-youtube-thumbnail

README.md
[![agentmods](https://agentmods.dev/badge/skills/samuraigpt/generative-media-skills/muapi-youtube-thumbnail/github.svg)](https://agentmods.dev/skills/samuraigpt/generative-media-skills/muapi-youtube-thumbnail)
Your own site
<a href="https://agentmods.dev/skills/samuraigpt/generative-media-skills/muapi-youtube-thumbnail"><img src="https://agentmods.dev/badge/skills/samuraigpt/generative-media-skills/muapi-youtube-thumbnail/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 muapi-youtube-thumbnail

Your own site · 80×15
<a href="https://agentmods.dev/skills/samuraigpt/generative-media-skills/muapi-youtube-thumbnail"><img src="https://agentmods.dev/badge/skills/samuraigpt/generative-media-skills/muapi-youtube-thumbnail.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 30 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 815 The whole file, excluding the scripts and references it only reads on demand.
Security scan B 2 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • Socket pass 15 Jun 2026
  • Snyk pass 19 May 2026
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 2 findings, 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 Data Exfiltration · line 65
    Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.
    Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
  • medium Data Exfiltration · line 65
    Data is being sent to an external URL. This could be legitimate telemetry or data exfiltration. Manual review is recommended.
    Fix: Verify the destination URL is trusted and necessary. Remove or replace with documented APIs. Ensure no secrets, tokens, or PII are transmitted.
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 $0.00030 $0.00815
Opus 5 $0.00015 $0.00407
Sonnet 5 $0.00006 $0.00163
Haiku 4.5 $0.00003 $0.00081

Measured 12d ago against content hash c5a8a08d04c0, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade B, and why

muapi-youtube-thumbnail scanned grade B with 2 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 12d 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.

Sends data to an external URLmediumData exfiltration

A POST to an outside endpoint may be telemetry or may be exfiltration; either way the mod talks to somewhere, and you should know where.

- For model IDs without a CLI alias yet, fall back to the raw endpoint via `curl -X POST https://api.muapi.ai/api/v1/<endpoint> -H "x-api-key: $MUAPI_API_KEY" -H 'content-type: application/json' -d '{...}'` and poll with

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

- For model IDs without a CLI alias yet, fall back to the raw endpoint via `curl -X POST https://api.muapi.ai/api/v1/<endpoint> -H "x-api-key: $MUAPI_API_KEY" -H 'content-type: application/json' -d '{...}'` and poll with
Origin

Copies of this mod

1 near-identical copy found in the catalogue:

.opencode/skills/muapi-youtube-thumbnail/SKILL.md · 67 lines

How it starts

The opening of the file, as written. The whole thing — 67 lines — stays where its author put it; the contents beside it link to each section on GitHub.

YouTube Thumbnail

Design a high-CTR YouTube thumbnail — striking imagery, bold text placement, and emotional face/subject if needed.

Inputs

Name Type Required Default Description
title text yes The video title or topic (e.g. "I tried 7 AI tools in 24 hours — here's what happened").
channel_style text no bold, high contrast, bright colors, clean design, YouTube tech aesthetic Channel brand style (e.g. "dark moody gaming", "bright educational", "minimal corporate").
subject_description text no Optional description of the person or subject to feature (e.g. "a surprised young man in a hoodie").

Steps

Thumbnails are the #1 factor in YouTube CTR. Generate a single, maximum-impact 16:9 image.

Phase A — Plan the composition

Before generating, briefly reason about the best thumbnail formula for this topic:

  • Emotion-first: shocked/curious face if relevant + bold text = high CTR
  • Text overlay: 3–5 words max, high-contrast (white/yellow on dark, or vice-versa)
  • Contrast & saturation: thumbnails compete in a grid — they must pop

Phase B — Generate the thumbnail

  1. Build the image generation prompt:
    • Subject: {{subject_description}} if provided, otherwise design an object/scene that dramatizes the topic.
    • Mood: derives from {{channel_style}}.
    • Composition: rule-of-thirds, subject on left or right with empty space for text.
    • Style tags: {{channel_style}}, youtube thumbnail composition, ultra detailed, vibrant, high contrast, 16:9.
  2. Call muapi image generate (model=gpt-image-2-text-to-image, aspect_ratio=16:9).

Phase C — Text overlay guidance

After generation, return:

  • Suggested overlay text: 3–5 bold words that complement the title {{title}}.
  • Text placement: where on the canvas to position text (e.g. "bold yellow text, top-right third").
  • Font recommendation: style suggestion (e.g. "Impact-style all-caps with black outline").

Read the full file on GitHub · 67 lines

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. 12d ago First seen · 67 lines · 30 tokens per session scan B c5a8a08d04c0

Subscribe to this mod's changes

muapi-youtube-thumbnail is a skill published in the GitHub repository SamurAIGPT/Generative-Media-Skills (4,259 stars, last pushed 3d ago), licensed MIT. It adds 30 tokens to every session and 815 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it B with 2 findings (sends data to an external url, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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