YouTube Thumbnail
SkillMediaLets your agent design eye-catching YouTube thumbnails with bold text and imagery.
Available today. Use it from your connected AI after setup.
No other account needed.
Connect ahel once, and every AI you use reads what you have installed.
Then ask your AI: use the YouTube Thumbnail skill
About this capability
Design a high-CTR YouTube thumbnail — striking imagery, bold text placement, and emotional face/subject if needed.
What this skill tells your AI
The instructions your AI receives, as published by samuraigpt/generative-media-skills in library/visual/youtube-thumbnail/SKILL.md and read by ahel’s review.
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
- 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.
- Subject:
- 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").
Notes
- Never put too much text in the prompt — text rendering in image models is unreliable. Guide the user on adding text in post-production (Canva, Photoshop).
- If the user already has a channel image or face photo in the session, use
muapi image editto incorporate it. - Suggest A/B variants only if the user asks.
Trigger Keywords
youtube thumbnail, yt thumbnail, thumbnail, video thumbnail, youtube cover
Notes for the Executing Agent
- This recipe is LLM-orchestrated: read each phase, gather any missing inputs from the user, then call
muapiCLI commands. Usemuapi auth configurefirst ifMUAPI_API_KEYis unset. - 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 withmuapi predict wait <request_id>. - Substitute
{{input_name}}placeholders with the user's actual inputs before issuing each call.
Signals
- GitHub stars
- 4k
- Forks
- 489
- Last commit
- Sep 2026
ahel recommends instead
Advanced
- Catalog kind
- skill
- Gateway key
muapi-youtube-thumbnail-samuraigpt- Source
- github.com/samuraigpt/generative-media-skills