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.
npx skills add martineserios/thebrana --skill first-principlesgit clone --depth 1 https://github.com/martineserios/thebranaWrote 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/skills/martineserios/thebrana/first-principles)<a href="https://agentmods.dev/skills/martineserios/thebrana/first-principles"><img src="https://agentmods.dev/badge/skills/martineserios/thebrana/first-principles/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/skills/martineserios/thebrana/first-principles"><img src="https://agentmods.dev/badge/skills/martineserios/thebrana/first-principles.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 | $0.00099 | $0.04271 |
| Opus 5.5 | $0.00040 | $0.01708 |
| Sonnet 5.5 | $0.00020 | $0.00854 |
| Haiku 4.5 | $0.00010 | $0.00427 |
Grade A, and why
first-principles 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.
This is a copy
100% identical to first-principles — 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.
How it starts
The opening of the file, as written. The whole thing — 629 lines — stays where its author put it; the contents beside it link to each section on GitHub.
First Principles Thinking
Break down complex problems to their fundamental truths, then reason up from there. Master Aristotle's ancient method modernized by Elon Musk to solve seemingly impossible problems.
When to Use This Skill
- Facing a "impossible" problem where conventional solutions don't work
- Challenging industry assumptions that everyone accepts as truth
- Pricing or cost analysis to find dramatic savings (like Musk with batteries)
- Product innovation when iterating on existing solutions isn't enough
- Strategic decisions where analogies to other companies may mislead
- Breaking through mental blocks when you're stuck in conventional thinking
Methodology Foundation
| Aspect | Details |
|---|---|
| Source | Aristotle (384-322 BC), modernized by Elon Musk |
| Expert | Aristotle called it "the first basis from which a thing is known"; Musk applies it to SpaceX, Tesla, and every venture |
| Core Principle | "Boil things down to the most fundamental truths and say, 'What are we sure is true?'... and then reason up from there." - Elon Musk |
What Claude Does vs What You Decide
"Claude structures the breakdown. You challenge the assumptions."
| Claude handles | You provide |
|---|---|
| Systematically listing assumptions | Domain expertise to validate/invalidate |
| Breaking down atomic components | Real-world cost/constraint data |
| Applying the physics vs convention test | Judgment on what's truly immutable |
| Structuring the rebuild from fundamentals | Strategic decisions on which path to pursue |
| Generating novel solution frameworks | Feasibility assessment and implementation |
Remember: First principles is a thinking tool. Claude accelerates the structure; breakthrough insights come from YOUR willingness to question everything.
What This Skill Does
- Deconstructs assumptions - Identifies what you think is true vs. what IS true
- Reveals hidden constraints - Exposes artificial limitations masquerading as laws
- Enables breakthrough solutions - Creates paths invisible to analogical thinkers
- Reduces costs dramatically - Finds the true floor price of anything
- Builds original insights - Generates conclusions others can't reach by copying
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.
- 1mo ago First seen · 629 lines · 99 tokens per session scan A 697805728775
first-principles is a skill published in the GitHub repository martineserios/thebrana (3 stars, last pushed yesterday), licensed MIT. It adds 99 tokens to every session and 4,271 once invoked, about $0.0004 per session on Opus 5.5. A static security scan graded it A with 0 findings. It is 100% identical to first-principles, differing in 0 lines, and is treated as a copy.
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