Skill-creator can generate a malformed YAML

[nodakai]

My case involved a YAML key–value pair with an unquoted colon in the value. Neither Codex Desktop nor the VS Code extension flagged it, and I only discovered the issue after running the Codex CLI

[EngineerNV]

ok so i think i know what is happening - your frontmatter or The top of your skill.MD file looks like this:

---
name: skill-foo
description: a working yaml frontmatter
---

The problem is that in the YAML section of that SKILL.MD, the colon is treated as a delimiter for fields in the YAML. So if your codex session generated a ':' inside of the description or any other field it will trigger the error thinking your frontmatter has extra fields. Example:

---
name: skill-fail
description: a bad frontmatter that will: break, think that will is a key and this entire sentence is the key
---

What you should do is look at your skill.md file that is causing you problems and either: delete the extra :

1. delete the extra ':'
2. put the entire description within quotes.
   ---
name: skill-fail-fix
description: "a bad frontmatter that will: break, think that will is a key and this entire sentence is the value"
---

The CLI is stricter with enforcing this than the desktop app - so that explains why you found the issue there instead of the higher UI interfaces.