spec-author

spec-author is a skill for Claude Code, Codex from Chemaclass/agnostic-ai. It costs 39 tokens per session (255 once invoked), scanned A, original, MIT.

A writing guide for adding a new agent, skill, rule, or hook specification to an agnostic-ai project.

In plain words
What is it for?
Use it to turn a description into a Markdown or YAML specification, validate it, and preview the generated files.
Why use it?
It removes the guesswork about file locations, formats, and required checks when creating a new specification.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it to turn a description into a Markdown or YAML specification, validate it, and preview the generated files.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/chemaclass/agnostic-ai/spec-author
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.

Any agent
npx skills add Chemaclass/agnostic-ai --skill spec-author
Clone the repo
git clone --depth 1 https://github.com/Chemaclass/agnostic-ai

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 spec-author

README.md
[![agentmods](https://agentmods.dev/badge/skills/chemaclass/agnostic-ai/spec-author/github.svg)](https://agentmods.dev/skills/chemaclass/agnostic-ai/spec-author)
Your own site
<a href="https://agentmods.dev/skills/chemaclass/agnostic-ai/spec-author"><img src="https://agentmods.dev/badge/skills/chemaclass/agnostic-ai/spec-author/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for spec-author

Your own site · 80×15
<a href="https://agentmods.dev/skills/chemaclass/agnostic-ai/spec-author"><img src="https://agentmods.dev/badge/skills/chemaclass/agnostic-ai/spec-author.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 39 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 255 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found 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 5.1 $0.00039 $0.00255
Opus 5 $0.00019 $0.00128
Sonnet 5 $0.00008 $0.00051
Haiku 4.5 $0.00004 $0.00026

Measured 10d ago against content hash ccfb1e2e8fe9, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

spec-author 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 10d 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.

.agnostic-ai/skills/spec-author/SKILL.md · 29 lines

What it actually says

spec-author

Authors a new agnostic-ai spec file from a description.

Steps

  1. Ask the user which kind: agent, skill, rule, or hook.
  2. Pick the right directory and extension:
    • agent: agents/<name>.md
    • skill: skills/<name>/SKILL.md
    • rule: rules/<name>.md
    • hook: hooks/<name>.yaml
  3. Build the YAML frontmatter (or full YAML for hooks) per docs/user/spec-format.md.
  4. Write the body in plain English. Lead with the action.
  5. Run agnostic-ai validate to confirm parse.
  6. Run agnostic-ai sync --dry-run to preview emitted outputs.

Conventions

  • name field matches the file name without extension.
  • description is one short sentence.
  • Body is markdown. Avoid em dashes. Avoid filler.
  • Hooks include a command field with the exact shell to run.
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. 10d ago First seen · 29 lines · 39 tokens per session scan A ccfb1e2e8fe9

Subscribe to this mod's changes

spec-author is a skill published in the GitHub repository Chemaclass/agnostic-ai (12 stars, last pushed today), licensed MIT. It adds 39 tokens to every session and 255 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.