Borrowing it
Nothing to install: this file belongs to jessepinkman9900/claude-second-brain. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/jessepinkman9900/claude-second-brain/main/CLAUDE.mdgit clone --depth 1 https://github.com/jessepinkman9900/claude-second-brainWrote 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.
[](https://agentmods.dev/instructions/jessepinkman9900/claude-second-brain/claude-md)<a href="https://agentmods.dev/instructions/jessepinkman9900/claude-second-brain/claude-md"><img src="https://agentmods.dev/badge/instructions/jessepinkman9900/claude-second-brain/claude-md/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.
<a href="https://agentmods.dev/instructions/jessepinkman9900/claude-second-brain/claude-md"><img src="https://agentmods.dev/badge/instructions/jessepinkman9900/claude-second-brain/claude-md.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.03260 | $0.03260 |
| Opus 5 | $0.01630 | $0.01630 |
| Sonnet 5 | $0.00652 | $0.00652 |
| Haiku 4.5 | $0.00326 | $0.00326 |
Grade A, and why
claude-second-brain CLAUDE.md 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 9d 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.
How it starts
The opening of the file, as written. The whole thing — 254 lines — stays where its author put it; the contents beside it link to each section on GitHub.
LLM Wiki — Schema & Operating Instructions
This file governs how Claude Code maintains the personal knowledge wiki in this vault. Read it at the start of every session before doing any wiki work.
What This Wiki Is
This is a persistent, compounding knowledge base — not a RAG index. When you add a source, Claude reads it, extracts key knowledge, and integrates it into interlinked wiki pages. The wiki accumulates understanding over time; cross-references, contradictions, and syntheses are already there when you need them.
You (the human) are responsible for: sourcing material, exploration, and asking the right questions. Claude is responsible for: summarizing, cross-referencing, filing, and maintaining the wiki.
Directory Layout
claude-second-brain/
├── CLAUDE.md ← This file. The schema.
├── raw-sources/ ← Raw source material. IMMUTABLE — Claude never modifies these.
│ ├── articles/ ← Web articles saved as markdown
│ ├── pdfs/ ← PDF files or extracted text
│ └── personal/ ← Personal notes flagged for ingestion
├── wiki/ ← LLM-maintained knowledge base. Claude owns this entirely.
│ ├── index.md ← Master index of all wiki pages
│ ├── log.md ← Running log of all wiki activity
│ ├── overview.md ← Evolving high-level synthesis
│ ├── sources/ ← One summary page per ingested source
│ ├── qa/ ← Filed answers to notable queries
│ └── [topic/entity pages at root of wiki/]
└── [existing vault files] ← Daily notes, misc, ideas, etc. Claude never touches these.
Page Types
overview — wiki/overview.md
The single evolving synthesis page. Updated when a new source meaningfully shifts the overall picture. Structured as a narrative with cross-links, not a list.
topic — wiki/[kebab-name].md
Notes on a concept, technology, domain, or idea. Examples: wiki/distributed-systems.md, wiki/machine-learning-ops.md, wiki/investing-frameworks.md.
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.
- 9d ago First seen · 254 lines · 3,260 tokens per session scan A a11e58b8a0e1
claude-second-brain CLAUDE.md is an instructions file published in the GitHub repository jessepinkman9900/claude-second-brain (47 stars, last pushed 4mo ago), licensed MIT. It adds 3,260 tokens to every session, about $0.0163 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.
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