samuraigpt/generative-media-skills1 file

Muapi Youtube Thumbnail

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

Specification
Skill ID
samuraigpt/generative-media-skills/muapi-youtube-thumbnail
Publisher
samuraigpt
Repository
generative-media-skills
Installs
0
Files
1
Synced
Sep 23, 2026
How to use it

Open any RiverX project, open the Skills panel in the chat, and search for this identifier. The files are fetched from the source repository at install time.

samuraigpt/generative-media-skills/muapi-youtube-thumbnailInstalls these files
  • SKILL.md

What this skill tells the agent

YouTube Thumbnail

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

Inputs

NameTypeRequiredDefaultDescription
titletextyes—The video title or topic (e.g. "I tried 7 AI tools in 24 hours — here's what happened").
channel_styletextnobold, high contrast, bright colors, clean design, YouTube tech aestheticChannel brand style (e.g. "dark moody gaming", "bright educational", "minimal corporate").
subject_descriptiontextno—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.
  1. 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 edit to 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 muapi CLI commands. Use muapi auth configure first if MUAPI_API_KEY is 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 with muapi predict wait <request_id>.
  • Substitute {{input_name}} placeholders with the user's actual inputs before issuing each call.

Use this skill in a project

Open any RiverX project, search the Skills panel for samuraigpt/generative-media-skills/muapi-youtube-thumbnail, and install it in one click.

Use this skill