authoring-skills-and-rules

authoring-skills-and-rules is a skill for Claude Code from afaraha8403/balakit. It costs 156 tokens per session (3,894 once invoked), scanned A, original, MIT.

A practical guide to writing Skills and rules for coding agents across Claude Code, Cursor, OpenCode, Codex, and GitHub Copilot. Skills are on-demand procedures; rules are standing instructions.

In plain words
What is it for?
Use it to design file layouts, activation rules, descriptions, shared references, and platform-specific versions of agent instructions.
Why use it?
It helps authors choose the right instruction type and keep behavior consistent across supported coding-agent platforms.

Skill for Claude Code

Written for Claude Code: disable-model-invocation in frontmatter. Also seen: reads .claude/ paths; mentions CLAUDE.md; mentions subagents.

Good fit Use it to design file layouts, activation rules, descriptions, shared references, and platform-specific versions of agent instructions.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/afaraha8403/balakit/authoring-skills-and-rules
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 afaraha8403/balakit --skill authoring-skills-and-rules
Clone the repo
git clone --depth 1 https://github.com/afaraha8403/balakit

Made for: Claude Code.

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 authoring-skills-and-rules

README.md
[![agentmods](https://agentmods.dev/badge/skills/afaraha8403/balakit/authoring-skills-and-rules/github.svg)](https://agentmods.dev/skills/afaraha8403/balakit/authoring-skills-and-rules)
Your own site
<a href="https://agentmods.dev/skills/afaraha8403/balakit/authoring-skills-and-rules"><img src="https://agentmods.dev/badge/skills/afaraha8403/balakit/authoring-skills-and-rules/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 authoring-skills-and-rules

Your own site · 80×15
<a href="https://agentmods.dev/skills/afaraha8403/balakit/authoring-skills-and-rules"><img src="https://agentmods.dev/badge/skills/afaraha8403/balakit/authoring-skills-and-rules.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 156 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,894 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 $0.00156 $0.03894
Opus 5 $0.00078 $0.01947
Sonnet 5 $0.00031 $0.00779
Haiku 4.5 $0.00016 $0.00389

Measured today against content hash ba1218707a3e, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

authoring-skills-and-rules 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 today.

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.

.agents/skills/authoring-skills-and-rules/SKILL.md · 322 lines

How it starts

The opening of the file, as written. The whole thing — 322 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Authoring Skills and Rules (cross-platform)

Leading words: progressive disclosure, context pointer, token budget, Apply-when description, playbook todos, skip reason, leading words, phase separation, encode lessons in structure, deletion test.

A practitioner's guide to writing and maintaining the two artifact families that steer coding agents — Skills (on-demand, procedural capabilities) and Rules / instructions (standing context) — across Claude Code, Cursor, OpenCode, Codex, and GitHub Copilot.

Trigger: /authoring-skills-and-rules, or any request to write, port, or review a Skill or rule. If the target platform(s) are unstated, ask before scaffolding — the file layout differs per platform.

This skill carries the per-platform exact details in references/ (loaded on demand). The body below is the decision model + the universal craft + a phase-separated workflow.


The one decision that comes first: Skill vs Rule

Pick the artifact by how the behavior should load, not by topic.

Skill (SKILL.md) Rule / instructions
Loads On demand — only when the task matches its description Standing — always, or auto-attached by file glob
Cost ~Free until triggered (only the description is always in context) Taxes every request it applies to
Best for Multi-step procedures, reusable workflows, domain playbooks Project facts, coding standards, guardrails, style
Analogy A specialist you call in House rules pinned to the wall
Portable as One folder, near-identical across 4 of 5 platforms Format differs sharply per platform

Rules of thumb:

  • Procedure or workflow → Skill. If it has steps, checkpoints, or scripts.
  • Always-true fact or guardrail → Rule. "We use Vitest", "never commit secrets", "this repo is a monorepo".
  • A standing block that grew past a few paragraphs and became procedural → graduate it from the rule/CLAUDE.md into a Skill.
  • One capability per Skill. If the description needs "and" to cover unrelated jobs, split it.

Read the full file on GitHub · 322 lines

Files

What ships with it

6 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

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. today Changed · +36 lines · +24 tokens per session ba1218707a3e
  2. 11d ago First seen · 286 lines · 132 tokens per session scan A bf860a0f1075

Subscribe to this mod's changes

authoring-skills-and-rules is a skill published in the GitHub repository afaraha8403/balakit (1 stars, last pushed today), licensed MIT. It adds 156 tokens to every session and 3,894 once invoked, about $0.0008 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 2026-08-31.