Agent skill

Youtube Thumbnails

This skill should be used when the user asks to "create YouTube thumbnails", "generate thumbnails", "make video thumbnails", or needs AI-generated thumbnail images via Google Gemini for YouTube…

MITAuto-check passedMedia & Creative

Install Youtube Thumbnails

skills CLI

$ npx skills add swyxio/skills --skill youtube-thumbnails -a claude-code

Project install by default; add -g for ~/.claude/skills/.

GitHub CLI

$ gh skill install swyxio/skills youtube-thumbnails --agent claude-code

Project scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).

Manual copy

$ git clone --depth 1 https://github.com/swyxio/skills.git skills-src && mkdir -p .claude/skills && cp -r skills-src/youtube-thumbnails .claude/skills/youtube-thumbnails && rm -rf skills-src

Use ~/.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/

Paste into Claude Code

Install the "youtube-thumbnails" agent skill from https://github.com/swyxio/skills/tree/main/youtube-thumbnails into .claude/skills/youtube-thumbnails/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "youtube-thumbnails", 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

$skill-installer install https://github.com/swyxio/skills/tree/main/youtube-thumbnails

Type 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.

skills CLI

$ npx skills add swyxio/skills --skill youtube-thumbnails -a codex

Project install goes to .agents/skills/; add -g for ~/.codex/skills/.

GitHub CLI

$ gh skill install swyxio/skills youtube-thumbnails --agent codex

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/swyxio/skills.git skills-src && mkdir -p .agents/skills && cp -r skills-src/youtube-thumbnails .agents/skills/youtube-thumbnails && rm -rf skills-src

Use ~/.agents/skills/ instead of .agents/skills for a personal install.

Codex skills documentation · loads skills from .agents/skills/

Paste into Codex

Install the "youtube-thumbnails" agent skill from https://github.com/swyxio/skills/tree/main/youtube-thumbnails into .agents/skills/youtube-thumbnails/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "youtube-thumbnails", 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.

skills CLI

$ npx skills add swyxio/skills --skill youtube-thumbnails -a cursor

Project install goes to .agents/skills/; add -g for ~/.cursor/skills/.

GitHub CLI

$ gh skill install swyxio/skills youtube-thumbnails --agent cursor

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/swyxio/skills.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/youtube-thumbnails .cursor/skills/youtube-thumbnails && rm -rf skills-src

Use ~/.cursor/skills/ instead of .cursor/skills for a personal install.

Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/

Paste into Cursor

Install the "youtube-thumbnails" agent skill from https://github.com/swyxio/skills/tree/main/youtube-thumbnails into .cursor/skills/youtube-thumbnails/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "youtube-thumbnails", 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

$ gemini skills install https://github.com/swyxio/skills.git --path youtube-thumbnails

--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.

skills CLI

$ npx skills add swyxio/skills --skill youtube-thumbnails -a gemini-cli

Project install goes to .agents/skills/; add -g for ~/.gemini/skills/.

GitHub CLI

$ gh skill install swyxio/skills youtube-thumbnails --agent gemini-cli

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/swyxio/skills.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/youtube-thumbnails .gemini/skills/youtube-thumbnails && rm -rf skills-src

Use ~/.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/

Paste into Gemini CLI

Install the "youtube-thumbnails" agent skill from https://github.com/swyxio/skills/tree/main/youtube-thumbnails into .gemini/skills/youtube-thumbnails/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "youtube-thumbnails", 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.

GitHub CLI

$ gh skill install swyxio/skills youtube-thumbnails

Installs 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).

skills CLI

$ npx skills add swyxio/skills --skill youtube-thumbnails -a github-copilot

Project install goes to .agents/skills/; add -g for ~/.copilot/skills/.

Manual copy

$ git clone --depth 1 https://github.com/swyxio/skills.git skills-src && mkdir -p .github/skills && cp -r skills-src/youtube-thumbnails .github/skills/youtube-thumbnails && rm -rf skills-src

Use ~/.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/

Paste into GitHub Copilot

Install the "youtube-thumbnails" agent skill from https://github.com/swyxio/skills/tree/main/youtube-thumbnails into .github/skills/youtube-thumbnails/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "youtube-thumbnails", 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.

skills CLI

$ npx skills add swyxio/skills --skill youtube-thumbnails -a opencode

OpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.

GitHub CLI

$ gh skill install swyxio/skills youtube-thumbnails --agent opencode

Project scope by default (.agents/skills/); add --scope user for a personal install.

Manual copy

$ git clone --depth 1 https://github.com/swyxio/skills.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/youtube-thumbnails .opencode/skills/youtube-thumbnails && rm -rf skills-src

Use ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.

OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/

Paste into OpenCode

Install the "youtube-thumbnails" agent skill from https://github.com/swyxio/skills/tree/main/youtube-thumbnails into .opencode/skills/youtube-thumbnails/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "youtube-thumbnails", 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: youtube-thumbnails
GitHub stars: 176
Token cost: ~1.6k tokens
SKILL.md length: 526 words
Files: 1
Skills in repo: 89
Repo updated: Oct 5, 2026
First seen: Oct 7, 2026
Licence: MIT

At a glance

This skill should be used when the user asks to "create YouTube thumbnails", "generate thumbnails", "make video thumbnails", or needs AI-generated thumbnail images via Google Gemini for YouTube…

Works in 7 steps: Gather Video Info → Navigate to Gemini → Craft the Thumbnail Prompt → …
Asks to create YouTube thumbnails
SKILL.md covers Overview, Step-by-Step Workflow, File Size Reference and Example Prompts, plus 1 more section
Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md

What it does

Youtube Thumbnails is an agent skill from swyxio/skills. This skill should be used when the user asks to "create YouTube thumbnails", "generate thumbnails", "make video thumbnails", or needs AI-generated thumbnail images via Google Gemini for YouTube videos. Covers prompt engineering, image generation, compression, and upload to YouTube Studio.

Its SKILL.md is about 1.6k tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.

It sits in Media & Creative, covering Image generation. It works with YouTube and Google Gemini. The repository describes itself as: Agent skills for Claude Code and other AI agents. The licence is MIT.

When your agent uses it

Asks to create YouTube thumbnails
Generate thumbnails
Make video thumbnails
Needs AI-generated thumbnail images via Google Gemini for YouTube videos

Example prompts

“create YouTube thumbnails”
“generate thumbnails”
“make video thumbnails”
“/youtube-thumbnails”

Workflow steps

7 steps, taken from the step headings in SKILL.md.

Gather Video Info
Navigate to Gemini
Craft the Thumbnail Prompt
Generate and Save
Compress to Under 2MB
Upload Thumbnails to YouTube Studio
Verify

What it can do on your machine

Read from SKILL.md and the folder at commit 038ef34. 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 bash and applescript).
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

Youtube Thumbnails loads about 1.6k tokens when it runs. Until then it costs about 77 tokens; SKILL.md has 526 words of instructions outside code blocks.

Always · name and description, kept in context so the agent knows when to use it: ~77
When it runs · the whole SKILL.md, loaded when a task matches: ~1.6k

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

The full file from swyxio/skills at commit 038ef34, republished under its MIT licence (© swyxio). 526 words, ~1,602 tokens.

Download SKILL.mdSave it as .claude/skills/youtube-thumbnails/SKILL.md (or your agent's skills folder).

name: youtube-thumbnails
description: This skill should be used when the user asks to "create YouTube thumbnails", "generate thumbnails", "make video thumbnails", or needs AI-generated thumbnail images via Google Gemini for YouTube videos. Covers prompt engineering, image generation, compression, and upload to YouTube Studio.
metadata.version: 0.1.0

YouTube Thumbnail Generation via Gemini

Overview

Generate custom YouTube thumbnails using Google Gemini's image generation (Pro mode). Each thumbnail is a 1280x720 image with bold text overlays, thematic visuals, and branding.

Step-by-Step Workflow

1. Gather Video Info

For each video that needs a thumbnail, collect:

Title (already set on YouTube)
Content type: "AI in Action" weekly jam or "Paper Club" reading
Topic summary: What was presented/demoed (from frame extraction or title)
Presenter name (optional, for subtitle text)
Date in D Mon YYYY format

2. Navigate to Gemini

Go to gemini.google.com
Click Tools button (bottom toolbar)
Enable Create images
Click the model dropdown (shows "Fast" by default) and select Pro
Confirm "Image" chip and "Pro" label appear in the chat input area

3. Craft the Thumbnail Prompt

Use this prompt template, customized per video:

Create a YouTube thumbnail (1280x720) for a video titled "[FULL TITLE]".
[1-2 sentences describing what the video is about — the demo, paper, or topic].
The visual should be [THEME DESCRIPTION]: [specific visual elements relevant to the topic].
Bold text overlay: "[MAIN TITLE]" prominently, with smaller text "[SUBTITLE]" below it.
Include a bottom bar with "[SERIES NAME] [D MON YYYY]" in bold.
Please include the Latent Space podcast logo in a corner — search the web for "Latent Space podcast logo" to find it.
Use [COLOR PALETTE] with a dark [THEME] background.

Prompt Customization by Content Type

AI in Action (demos/presentations):

Bottom bar text: AI IN ACTION [D MON YYYY]
Visual theme: Match the demo topic (space, gaming, dev tools, etc.)
Colors: Vibrant, exciting — neon blues, greens, purples, electric tones

Paper Club (paper readings):

Bottom bar text: PAPER CLUB [D MON YYYY]
Visual theme: Academic but engaging — neural networks, brain visualizations, formulas
Colors: Deep blue, orange, white — scholarly but modern
Main text: Paper acronym or short name (e.g., "SDPO")
Subtitle: Full paper name

Key Prompt Tips

Always ask Gemini to search the web for relevant logos and reference images
Specify 1280x720 dimensions explicitly
Request bold, large text for the main title — readable at thumbnail size
Include a colored bottom bar with the series name and date
Keep the background dark so text pops

4. Generate and Save

Submit the prompt and wait ~30-45 seconds for Pro mode generation
Click the generated image to expand it
Click Save to download to ~/Downloads
Generated files will be named Gemini_Generated_Image_[hash].jpeg

5. Compress to Under 2MB

YouTube requires thumbnails under 2MB. Gemini Pro images are typically 3-4MB.

bash

convert "Gemini_Generated_Image_[hash].jpeg" -resize 1280x720 -quality 85 thumb_[label].jpg

Naming convention: thumb_[abbreviated_date].jpg (e.g., thumb_jan31.jpg, thumb_feb7.jpg)

Show full SKILL.md (206 more words)Show less

6. Upload Thumbnails to YouTube Studio

For each video:

Go to YouTube Studio → Content → click on the video
Click the pencil/edit icon (Details tab) in the left sidebar
Scroll to the Thumbnail section
Click the Upload file button (may be hidden — use find tool to locate ref)
Select the correct thumb_[date].jpg file
Verify the thumbnail appears in the preview
Click Save at the top right

File picker automation (macOS): After clicking Upload file, use osascript to navigate the native file dialog:

applescript

tell application "System Events"
    delay 1
    keystroke "g" using {command down, shift down}
    delay 1
    keystroke "/path/to/thumb_[date].jpg"
    delay 0.5
    keystroke return
    delay 1
    keystroke return
end tell

7. Verify

Take a screenshot of each video's details page to confirm the custom thumbnail is set.

File Size Reference

Gemini Pro raw output: ~3-4MB (too large)
After convert -resize 1280x720 -quality 85: ~200-250KB (well under 2MB limit)
YouTube max thumbnail size: 2MB
YouTube thumbnail dimensions: 1280x720 (16:9)
Accepted formats: JPG, PNG, GIF

Example Prompts

Tech Demo Thumbnail

Create a YouTube thumbnail (1280x720) for a video titled "SpaceMolt - AI Agents in Multiplayer Space Games".
This is about a demo of SpaceMolt, a multiplayer space trading and mining game where AI agents autonomously play alongside human players.
The visual should be exciting and space-themed: spaceships, asteroids, neon glow, a dark cosmic background.
Bold text overlay: "SPACEMOLT" prominently, with smaller text "AI AGENTS IN SPACE GAMES" below it.
Include a bottom bar with "AI IN ACTION 7 FEB 2026" in bold.
Please include the Latent Space podcast logo in a corner — search the web for "Latent Space podcast logo".
Use vibrant sci-fi colors — electric blue, green, purple neon tones.

Academic Paper Thumbnail

Create a YouTube thumbnail (1280x720) for a video titled "RL via Self-Distillation (SDPO) Paper Reading".
This is an academic paper reading session about SDPO — Self-Distillation Preference Optimization.
The visual should be academic but engaging: neural network or brain visualization with mathematical formulas.
Bold text overlay: "SDPO" prominently, with smaller text "SELF-DISTILLATION PREFERENCE OPTIMIZATION" below it.
Include a bottom bar with "PAPER CLUB 12 FEB 2026" in bold.
Please include the Latent Space podcast logo in a corner — search the web for "Latent Space podcast logo".
Use deep blue, orange, and white color palette with a dark academic-themed background.

Troubleshooting

"File is bigger than 2MB": Compress with ImageMagick convert -resize 1280x720 -quality 85
Gemini generation takes long: Pro mode takes 30-45 seconds. Wait and check with a screenshot.
Upload button not visible: Use the find tool to locate the hidden "Upload file" button by ref.
File picker automation fails: Instruct user to manually select the file.

Files

Just SKILL.md in youtube-thumbnails of swyxio/skills.

Open the folder on GitHubat commit 038ef34

Compare with similar skills

Youtube Thumbnails 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.

Youtube Thumbnails compared with similar skills
Skill	Stars	Used in	Tokens	Auto-check	Licence	Repo updated
Youtube Thumbnails this skillswyxio/skills	176	—	~1.6k	Automated safety check: Pass	MIT	6 days ago
Nano Bananakkoppenhaver/cc-nano-banana	378	1 repos	~1.4k	Automated safety check: Pass	MIT	4 mo ago
Generate Youtube Thumbnailkrusemediallc/arcads-claude-code	1.6k	—	~2.4k	Automated safety check: Notes	MIT	18 days ago
Youtube Thumbnailhassancs91/claude-youtube-editor	328	—	~2.1k	Automated safety check: Notes	MIT	1 mo ago
Nano Bananajh941213/my-cc-harness	125	—	~1k	Automated safety check: Pass	None	2 mo ago
Nano Bananajh941213/my-cc-harness	125	—	~1.6k	Automated safety check: Notes	None	2 mo ago

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Questions about Youtube Thumbnails

What does Youtube Thumbnails do?

This skill should be used when the user asks to "create YouTube thumbnails", "generate thumbnails", "make video thumbnails", or needs AI-generated thumbnail images via Google Gemini for YouTube…. Youtube Thumbnails is an agent skill from swyxio/skills. This skill should be used when the user asks to "create YouTube thumbnails", "generate thumbnails", "make video thumbnails", or needs AI-generated thumbnail images via Google Gemini for YouTube videos.

When should I use Youtube Thumbnails?

Youtube Thumbnails fits situations like: asks to create YouTube thumbnails; generate thumbnails; make video thumbnails; needs AI-generated thumbnail images via Google Gemini for YouTube videos.

How do I install Youtube Thumbnails in Claude Code?

Run `npx skills add swyxio/skills --skill youtube-thumbnails -a claude-code`. Or copy the skill folder (youtube-thumbnails in swyxio/skills) into .claude/skills/youtube-thumbnails in your project. Claude Code loads it when a task matches its description.

How do I install Youtube Thumbnails in Codex?

Run `npx skills add swyxio/skills --skill youtube-thumbnails -a codex`. Or copy the skill folder (youtube-thumbnails in swyxio/skills) into .agents/skills/youtube-thumbnails in your project. Codex loads it when a task matches its description.

Can I use Youtube Thumbnails 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 swyxio/skills --skill youtube-thumbnails -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/youtube-thumbnails, .gemini/skills/youtube-thumbnails, .github/skills/youtube-thumbnails and .opencode/skills/youtube-thumbnails in your project.

What does Youtube Thumbnails need to run?

SKILL.md names no scripts, command-line tools or credentials: Youtube Thumbnails is instructions for the agent only.

Does Youtube Thumbnails 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 Youtube Thumbnails 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 Youtube Thumbnails use?

Youtube Thumbnails is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.

How many tokens does Youtube Thumbnails use?

About 1.6k tokens (SKILL.md is roughly 6.4k 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 Youtube Thumbnails?

Skills that share tags, products or a category with Youtube Thumbnails: Nano Banana (kkoppenhaver/cc-nano-banana, 378 stars), Generate Youtube Thumbnail (krusemediallc/arcads-claude-code, 1.6k stars), Youtube Thumbnail (hassancs91/claude-youtube-editor, 328 stars) and Nano Banana (jh941213/my-cc-harness, 125 stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.

Who maintains Youtube Thumbnails?

swyxio (a GitHub user) maintains it in swyxio/skills, which has 176 GitHub stars. The repository holds 89 skills in this directory. The repository was last updated on October 5, 2026.

Source: swyxio/skills on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.

Install Youtube Thumbnails

Facts

At a glance

What it does

When your agent uses it

Example prompts

Workflow steps

What it can do on your machine

Tool permissions

Runs code

Network

Credentials

Context cost

Safety

SKILL.md

YouTube Thumbnail Generation via Gemini

Overview

Step-by-Step Workflow

1. Gather Video Info

2. Navigate to Gemini

3. Craft the Thumbnail Prompt

Prompt Customization by Content Type

Key Prompt Tips

4. Generate and Save

5. Compress to Under 2MB

6. Upload Thumbnails to YouTube Studio

7. Verify

File Size Reference

Example Prompts

Tech Demo Thumbnail

Academic Paper Thumbnail

Troubleshooting

Files

Compare with similar skills

Similar skills

More from swyxio/skills

Related

Questions about Youtube Thumbnails