unknown-frontmatter-field SKILL.md skillB
unknown-frontmatter-field from agent-sh/agnix is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add agent-sh/agnix/unknown-frontmatter-field@git:20260214.d634c6ePins git:20260214.d634c6e in mdr.lock. Pin the fingerprint instead.
- Audit grade
- B, 16 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- agent-sh/agnix
- Path
tests/fixtures/invalid/skills/unknown-frontmatter-field/SKILL.md- Versions recorded
- 1
- Latest version
- git:20260214.d634c6e, committed Feb 14, 2026
- Size
- 144 bytes
- Repository stars
- 472
- License
- Apache-2.0
Use when validating frontmatter keys.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
Run frontmatter validation.
Read the whole file at its exact version.
How to install
mdr add agent-sh/agnix/unknown-frontmatter-field@sha256:484a65a0122aa70bThe line at the top of this page pins the label git:20260214.d634c6e, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_bmow3oyuhmznlrlw)
4 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 1 version of this file, committed on Feb 14, 2026.
Audit of the latest version
- fail: Size between 200 bytes and 200 KB (144 bytes)
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- 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
Starting a new one? Use a template for SKILL.md on mdpantry, which passes every one of these checks and says what to change in it.
Source
agent-sh/agnix · 472 stars · license Apache-2.0 · pushed 2026-11-07 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_bmow3oyuhmznlrlw GET https://markdownregistry.com/api/v1/resolve?ref=agent-sh/agnix/unknown-frontmatter-field GET https://markdownregistry.com/api/v1/blob/484a65a0122aa70bca7c63c6d36125be57c6e5d9c07112a570999b307ac86ab7
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.