second-brain

second-brain is a skill for Claude Code from sean-esk/second-brain-gtd. It costs 247 tokens per session (3,261 once invoked), scanned A, original, no licence file.

A personal knowledge-management system for Obsidian, a note-taking app. It combines GTD, a method for organising tasks, Zettelkasten, a method for linking ideas, and PARA, a way to arrange information by projects, areas, resources, and archives.

In plain words
What is it for?
Use it to capture thoughts, process an inbox, organise notes, and manage tasks in an Obsidian vault.
Why use it?
It gives captured thoughts and tasks a set of workflows for saving, processing, organising, and reviewing personal notes.

Skill for Claude Code

Written for Claude Code: installed under .claude/.

Good fit Use it to capture thoughts, process an inbox, organise notes, and manage tasks in an Obsidian vault.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/sean-esk/second-brain-gtd/second-brain
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 sean-esk/second-brain-gtd --skill second-brain
Clone the repo
git clone --depth 1 https://github.com/sean-esk/second-brain-gtd

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 second-brain

README.md
[![agentmods](https://agentmods.dev/badge/skills/sean-esk/second-brain-gtd/second-brain/github.svg)](https://agentmods.dev/skills/sean-esk/second-brain-gtd/second-brain)
Your own site
<a href="https://agentmods.dev/skills/sean-esk/second-brain-gtd/second-brain"><img src="https://agentmods.dev/badge/skills/sean-esk/second-brain-gtd/second-brain/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 second-brain

Your own site · 80×15
<a href="https://agentmods.dev/skills/sean-esk/second-brain-gtd/second-brain"><img src="https://agentmods.dev/badge/skills/sean-esk/second-brain-gtd/second-brain.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 247 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,261 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. Third-party audits
  • Socket pass 18 Mar 2026
  • Snyk pass 15 Feb 2026
How audits are shown
Origin unknown 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 $0.00247 $0.03261
Opus 5.5 $0.00099 $0.01304
Sonnet 5.5 $0.00049 $0.00652
Haiku 4.5 $0.00025 $0.00326

Measured 1mo ago against content hash cc46fcd250e2, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

second-brain 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 1mo 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.

.claude/skills/second-brain/SKILL.md · 399 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

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. 1mo ago First seen · 399 lines · 247 tokens per session scan A cc46fcd250e2

Subscribe to this mod's changes

second-brain is a skill published in the GitHub repository sean-esk/second-brain-gtd (53 stars, last pushed 10mo ago), with no licence file. It adds 247 tokens to every session and 3,261 once invoked, about $0.0010 per session on Opus 5.5. 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.

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