feynman

A learning aid for checking understanding, using questions to guide reasoning, and turning unclear engineering or product ideas into plans.

In plain words
What is it for?
Use it for Socratic learning, engineering explanations, product thinking, and early planning.
Why use it?
It helps reveal gaps in understanding and gives structure to ideas that are still vague.

Skill for Claude CodeCodex

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/sashajdn/dotf/feynman
Any agent
npx skills add sashajdn/dotf --skill feynman
Clone the repo
git clone --depth 1 https://github.com/sashajdn/dotf

Made for: Claude Code, Codex.

Per session 33 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,555 The whole file, excluding the scripts and references it only reads on demand.
Security scan B 1 finding. Scan, not verified.
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 $0.00033 $0.01555
Opus 5 $0.00016 $0.00777
Sonnet 5 $0.00007 $0.00311
Haiku 4.5 $0.00003 $0.00155

Measured 2d ago against content hash 382e70aeeb95, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade B, and why

feynman scanned grade B with 1 finding 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 2d 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.

Strips warnings and disclaimersmediumAnti-refusal

Omitting safety caveats hides risk from the user and is a common jailbreak preamble.

3. **Never lecture** - only ask questions that lead to discovery
agents/skills/feynman/SKILL.md · 236 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. 2d ago First seen · 236 lines · 33 tokens per session scan B 382e70aeeb95

Subscribe to this mod's changes

feynman is a skill published in the GitHub repository sashajdn/dotf (2 stars, last pushed 2d ago), with no licence file. It adds 33 tokens to every session and 1,555 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it B with 1 finding (strips warnings and disclaimers). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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