Mentarium Thinking Skills
12 ready-made skills that make Claude and ChatGPT reason with mental models, step by step, and hand you a clean result.
$29
One-time payment. Instant download link by email. 7-day refund, no questions.
What you get
- 12 Claude skills (SKILL.md) for Claude.ai, the Claude apps and Claude Code
- The same 12 as ChatGPT Custom GPT / Project instructions, plus a knowledge file with the Mentarium frameworks
- Install guide for both, in plain steps
- Personal and team use; edit them as you like
The 12 skills
- first-principles: break a problem down to basic truths and rebuild
- inversion: list how to fail, then turn it into a plan
- pre-mortem: imagine the project failed and rank the risks
- second-order: map consequences three levels out
- bias-audit: check a plan or text against the Bias Radar
- decision-loop: run a full decision and get a journal-ready summary
- steelman: build the best version of the other side
- opportunity-cost: compare paths by what each gives up
- priority-matrix: Eisenhower + Pareto on your task list
- five-whys: root cause analysis
- red-team: attack an idea or a strategy
- weekly-review: a weekly review run with models
Save with a bundle
Thinking Skills + Field Guide
$49 · save $-6
Mentarium Complete
$69 · save $3
Questions
Do I need a paid Claude or ChatGPT plan?
Skills work wherever your Claude plan supports skills; the ChatGPT versions need a plan that lets you create Custom GPTs or Projects. The files are plain Markdown, so you can also paste them into any assistant.
How is this different from the free Decision Coach?
The Decision Coach is a connector for guided decisions. The skills are 12 separate thinking moves you call by name, they work offline from any account, and you can edit them.
How do I get the files?
Right after paying you land on your downloads page, and we email you the same private link. Lost it? Resend it here.
Can I get a refund?
Yes, within 7 days of buying, for any reason. Reply to your order email or write to support@mentarium.io.