probe-metadata-values SKILL.md skillA
probe-metadata-values from agent-ecosystem/agent-skill-implementation is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add agent-ecosystem/agent-skill-implementation/probe-metadata-values@git:20260322.e2534ddPins git:20260322.e2534dd in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- agent-ecosystem/agent-skill-implementation
- Path
benchmark-skills/probe-metadata-values/SKILL.md- Versions recorded
- 1
- Latest version
- git:20260322.e2534dd, committed Mar 22, 2026
- Size
- 2,122 bytes
- Repository stars
- 6
- License
- CC-BY-4.0
Benchmark skill for testing how platforms handle edge-case YAML values in the metadata frontmatter field. Use when asked to probe metadata value handling.
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
# Metadata Value Edge Cases Probe
This skill tests whether platforms can successfully load a skill whose
`metadata` field contains edge-case YAML values. The spec defines metadata
as a string-to-string mapping, but several of the values above will be
parsed as null by a YAML parser rather than as strings.
## Canary Phrase
The canary phrase for this skill is: **THRUSH-FLINT-8294**
If you can see this phrase, the platform successfully loaded this skill
despite the edge-case metadata values.
## Instructions
When activated, report:
1. **Load success**: Did this skill load successfully? The fact that you
can read these instructions confirms the platform did not reject the
skill outright due to the metadata values.
2. **Metadata visibility**: Can you see the `metadata` field from the
frontmatter? If so, list each key and what value you see. Pay
particular attention to:
- `normal`: Should be the string `"baseline"` (control value).
- `empty-double` and `empty-single`: Should be empty strings.
- `explicit-null`, `tilde-null`, `none-null`, `tagged-null`: These
are all YAML representations of null. Report whether each appears
…Read the whole file at its exact version.
How to install
mdr add agent-ecosystem/agent-skill-implementation/probe-metadata-values@sha256:7d66815a0d8214a0The line at the top of this page pins the label git:20260322.e2534dd, 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_srhtgumipmrqdpe4)
2 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 1 version of this file, committed on Mar 22, 2026.
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (2122 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
agent-ecosystem/agent-skill-implementation · 6 stars · license CC-BY-4.0 · pushed 2026-09-27 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_srhtgumipmrqdpe4 GET https://markdownregistry.com/api/v1/resolve?ref=agent-ecosystem/agent-skill-implementation/probe-metadata-values GET https://markdownregistry.com/api/v1/blob/7d66815a0d8214a0dcfade063bd38538ecae94987ecb90f123fd226fefa87068
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.