sergebulaev/youtube-skills · .codex-marketplace/youtube-skills/skills/yt-thumbnail-brief/SKILL.md

yt-thumbnail-brief skillA

yt-thumbnail-brief is agent-read markdown (skill) from sergebulaev/youtube-skills: Turn a YouTube video idea into a designer-ready thumbnail brief: focal subject, face and emotion, a text overlay of 4 words or fewer that the title does not repeat, contrast and composition, and 2 to 3 A/B concepts for Test and Compare. Built on 2026 principles (one focal point, legible at 120 pixels, complements the title). Outputs the brief plus the Publora attach step (the image upload itself is out of band). Use to plan a thumbnail. Not for title words (use yt-title-optimizer)..

Indexed from public GitHub and served as immutable, content-addressed versions. Install it pinned to an exact SHA-256 with the mdr CLI, and every file is verified against the hash recorded here before it reaches your agent. The deterministic audit below grades the latest version, and the same file always earns the same grade.

How to install

Latest version
mdr add sergebulaev/youtube-skills/yt-thumbnail-brief@git:20260905.90a2ff2
Exact content
mdr add sergebulaev/youtube-skills/yt-thumbnail-brief@sha256:0751b25eb8356dd8

Pin to a label to follow the author's releases, or to a sha256 to freeze the exact bytes forever. Either way the resolved hash is written to mdr.lock, and mdr install reproduces it on any machine.

Badge

mdr badge

[![mdr](https://markdownregistry.com/badge/art_aphhte37tonytddv.svg)](https://markdownregistry.com/a/art_aphhte37tonytddv)

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Versions

versioncommittedcommitsizeaudit
git:20260905.90a2ff2 latest2026-09-05 90a2ff2 5,725 BA view · diff
git:20260702.23589082026-07-02 2358908 5,631 BA view

Audit of the latest version

A  17 of 17 checks passed. Deterministic, no model, same answer every run.
  • pass: Frontmatter block present
  • pass: Frontmatter declares a name
  • pass: Frontmatter declares a description
  • pass: Size between 200 bytes and 200 KB (5725 bytes)
  • pass: No zero-width or bidi control characters
  • pass: No instruction hidden inside an HTML comment
  • pass: No link to an exfiltration or paste host
  • pass: No credential-shaped string
  • pass: No instruction to send local credentials anywhere
  • pass: No text hidden with inline styles
  • pass: No prompt-injection phrasing
  • pass: No curl or wget piped into a shell
  • pass: No recursive delete of root, home or parent
  • pass: No instruction to read or print local credentials
  • pass: No base64 blob over 200 characters
  • pass: No link to a raw IP address
  • pass: No script tag

Source

GitHub

sergebulaev/youtube-skills · 12 stars · license MIT · pushed 2026-09-05 · branch main

API

GET https://markdownregistry.com/api/v1/artifacts/art_aphhte37tonytddv
GET https://markdownregistry.com/api/v1/resolve?ref=sergebulaev/youtube-skills/yt-thumbnail-brief
GET https://markdownregistry.com/api/v1/blob/0751b25eb8356dd860b3731e6f56510aef763335a4a87da67390f897e244cd8f