substack-note

substack-note is a skill for Claude Code, Codex from Rainbowlight-pixel/claude-cowork-content-plugin. It costs 36 tokens per session (516 once invoked), scanned A, a copy of substack-note, MIT.

A writing tool that turns long-form articles into short posts for Substack Notes, Substack’s social feed.

In plain words
What is it for?
Use it to create quick insights, questions, behind-the-scenes posts, opinions, teasers, and resource shares from newsletters or articles.
Why use it?
It saves you from finding and rewriting several shareable ideas from a finished article. It also helps keep short posts connected to the original content.

Skill for Claude CodeCodex

Part of the content-repurposing plugin — 7 skills, 6 commands shipped together

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/rainbowlight-pixel/claude-cowork-content-plugin/substack-note
Any agent
npx skills add Rainbowlight-pixel/claude-cowork-content-plugin --skill substack-note
Clone the repo
git clone --depth 1 https://github.com/Rainbowlight-pixel/claude-cowork-content-plugin

Made for: Claude Code, Codex.

Or install content-repurposing, the plugin that ships this one along with the rest of its 7 skills, 6 commands.

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 substack-note

README.md
[![agentmods](https://agentmods.dev/badge/skills/rainbowlight-pixel/claude-cowork-content-plugin/substack-note.svg)](https://agentmods.dev/skills/rainbowlight-pixel/claude-cowork-content-plugin/substack-note)
Your own site
<a href="https://agentmods.dev/skills/rainbowlight-pixel/claude-cowork-content-plugin/substack-note"><img src="https://agentmods.dev/badge/skills/rainbowlight-pixel/claude-cowork-content-plugin/substack-note.svg" alt="Measured on agentmods" height="20"></a>
Per session 36 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 516 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 $0.00036 $0.00516
Opus 5 $0.00018 $0.00258
Sonnet 5 $0.00007 $0.00103
Haiku 4.5 $0.00004 $0.00052

Measured 4d ago against content hash 47dea7822d98, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

substack-note 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 substack-note — 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.

content-repurposing/skills/substack-note/SKILL.md · 55 lines

How it starts

The opening of the file, as written. The whole thing — 55 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Substack Note Skill

You are a Substack content strategist who creates engaging Notes that build community, drive discussion, and funnel readers to longer content.

Process

Step 1: Analyze the Source

Read the source content and identify:

  • Key insights worth sharing as standalone thoughts
  • Behind-the-scenes moments or personal reflections
  • Questions that would spark discussion
  • Quick tips or tactical advice
  • Observations about trends or industry changes
  • Teasers for deeper content

Step 2: Generate Notes

Create 5-7 Substack Notes from the source. Each Note should be:

  • Length: 100-300 words (sweet spot for Notes engagement)
  • Tone: Conversational, like talking to a smart friend
  • Structure: Hook → Insight → Discussion prompt or CTA
Note Types to Include:
  1. The Quick Insight: One key lesson in 2-3 paragraphs
  2. The Question: Pose a thought-provoking question with context
  3. The Behind-the-Scenes: Share what didn't make it into the main content
  4. The Hot Take: A spicy opinion extracted from the content
  5. The Teaser: Preview of the longer content with a "read more" hook
  6. The Resource Share: Highlight a tool, framework, or resource from the content
  7. The Thread-Starter: Statement designed to generate comments and debate
For Each Note, Provide:
  • The full Note text, ready to post
  • A suggested posting time (Morning/Afternoon/Evening + day of week)
  • Expected engagement type (Likes, Comments, Restacks)
  • Whether it should link to longer content

Step 3: Save Output

Save all notes to a markdown file in the workspace folder. Name: substack-notes-[source-name].md Separate each note with a horizontal rule (---).

Quality Standards

  • Notes should feel authentic, not promotional
  • Each Note should stand completely on its own
  • Include at least 2 Notes that ask questions (drives comments)
  • At least 1 Note should be a teaser for longer content
  • Write in first person - Substack is personal
  • Avoid hashtags - Substack Notes don't use them

Read the full file on GitHub · 55 lines

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 · 55 lines · 36 tokens per session scan A 47dea7822d98

Subscribe to this mod's changes

substack-note is a skill published in the GitHub repository Rainbowlight-pixel/claude-cowork-content-plugin (6 stars, last pushed 4d ago), licensed MIT. It adds 36 tokens to every session and 516 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to substack-note, differing in 0 lines, and is treated as a copy.

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