no-frontmatter

no-frontmatter is a skill for Claude Code, Codex from code-yeongyu/senpi. It costs 0 tokens per session (15 once invoked), scanned A, a copy of no-frontmatter, MIT.

A skill file without the YAML metadata block normally placed at the top of a Markdown file. Its excerpt only repeats that it has no frontmatter.

In plain words
What is it for?
Use it for tests involving incomplete or non-standard skill files; no concrete coding task is documented.
Why use it?
It can expose how tooling handles skills that are missing expected metadata.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/code-yeongyu/senpi/no-frontmatter
Any agent
npx skills add code-yeongyu/senpi --skill no-frontmatter
Clone the repo
git clone --depth 1 https://github.com/code-yeongyu/senpi

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for no-frontmatter

README.md
[![agentmods](https://agentmods.dev/badge/skills/code-yeongyu/senpi/no-frontmatter.svg)](https://agentmods.dev/skills/code-yeongyu/senpi/no-frontmatter)
Your own site
<a href="https://agentmods.dev/skills/code-yeongyu/senpi/no-frontmatter"><img src="https://agentmods.dev/badge/skills/code-yeongyu/senpi/no-frontmatter.svg" alt="Measured on agentmods" height="20"></a>
Per session 0 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 15 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 100% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00000 $0.00015
Opus 5 $0.00000 $0.00008
Sonnet 5 $0.00000 $0.00003
Haiku 4.5 $0.00000 $0.00002

Measured 4d ago against content hash e5ca5b4ffb7a, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

no-frontmatter scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

100% identical to no-frontmatter — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

packages/coding-agent/test/fixtures/skills/no-frontmatter/SKILL.md · 4 lines

What it actually says

No Frontmatter

This skill has no YAML frontmatter at all.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 4d ago First seen · 4 lines · 0 tokens per session scan A e5ca5b4ffb7a

Subscribe to this mod's changes

no-frontmatter is a skill published in the GitHub repository code-yeongyu/senpi (419 stars, last pushed yesterday), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 15 tokens. A static security scan graded it A with 0 findings. It is 100% identical to no-frontmatter, differing in 0 lines, and is treated as a copy.