principle-redesign-from-first-principles

principle-redesign-from-first-principles is a skill for Claude Code from ericlitman/open-pstack. It costs 43 tokens per session (188 once invoked), scanned A, a copy of principle-redesign-from-first-principles, MIT.

A way to integrate a new requirement by redesigning around it as if it had been part of the original system.

In plain words
What is it for?
Use it when changing an existing feature, updating related types and documentation, or reshaping several connected parts of a codebase.
Why use it?
It avoids piling exceptions and adapters onto a design that was built for different assumptions.

Skill for Claude Code

Written for Claude Code: user-invocable in frontmatter.

Part of the pstack plugin — 52 skills, 12 agents, 1 hook shipped together

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/ericlitman/open-pstack/principle-redesign-from-first-principles
Any agent
npx skills add ericlitman/open-pstack --skill principle-redesign-from-first-principles
Clone the repo
git clone --depth 1 https://github.com/ericlitman/open-pstack

Made for: Claude Code.

Or install pstack, the plugin that ships this one along with the rest of its 52 skills, 12 agents, 1 hook.

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 principle-redesign-from-first-principles

README.md
[![agentmods](https://agentmods.dev/badge/skills/ericlitman/open-pstack/principle-redesign-from-first-principles.svg)](https://agentmods.dev/skills/ericlitman/open-pstack/principle-redesign-from-first-principles)
Your own site
<a href="https://agentmods.dev/skills/ericlitman/open-pstack/principle-redesign-from-first-principles"><img src="https://agentmods.dev/badge/skills/ericlitman/open-pstack/principle-redesign-from-first-principles.svg" alt="Measured on agentmods" height="20"></a>
Per session 43 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 188 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 89% copy Near-identical to another mod 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 $0.00043 $0.00188
Opus 5 $0.00022 $0.00094
Sonnet 5 $0.00009 $0.00038
Haiku 4.5 $0.00004 $0.00019

Measured 6d ago against content hash 8f500a2a89af, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-05, from the pricing page.

Security

Grade A, and why

principle-redesign-from-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 6d 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.

Origin

This is a copy

89% identical to principle-redesign-from-first-principles — 2 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.

plugins/pstack/skills/principle-redesign-from-first-principles/SKILL.md · 17 lines

What it actually says

Redesign From First Principles

When integrating a change, don't bolt it onto the existing design. Redesign as if the requirement had been there from the start. The result should look like what we would have built if we'd known on day one.

  • Read all affected files and understand the current design holistically
  • Ask: "if we were writing this from scratch with this new requirement, what would we build?"
  • Propagate the change through every reference: types, docs, examples, rationale sections
  • Think about the redesign holistically, then deliver it incrementally

This is the method for preserving option value when integrating changes into an existing design.

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. 6d ago First seen · 17 lines · 43 tokens per session scan A 8f500a2a89af

Subscribe to this mod's changes

principle-redesign-from-first-principles is a skill published in the GitHub repository ericlitman/open-pstack (216 stars, last pushed yesterday), licensed MIT. It adds 43 tokens to every session and 188 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 89% identical to principle-redesign-from-first-principles, differing in 2 lines, and is treated as a copy.

Related

Other skills, from other repositories

systematic-debugging

Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.

obra/superpowers · 21 tokens

local-ai-agents

Build local-first AI agents that run entirely on a developer workstation with Microsoft Foundry Local and Qwen function-calling models. Covers Small Language Models (SLMs), the OpenAI-compatible local endpoint, sandboxed local tools, local RAG with Chroma, local MCP servers, hybrid cloud/local routing, and the…

microsoft/ai-agents-for-beginners · 200 tokens

next-cache-components-adoption

Turn on Cache Components in a Next.js app and resolve the blocking routes it surfaces. Use when the user wants to enable, adopt, or migrate to Cache Components, flip the cacheComponents flag, work through a flood of blocking-prerender / instant validation errors, run the cache-components-instant-false codemod, or…

vercel/next.js · 95 tokens

next-cache-components-optimizer

Drive a Next.js route to instant navigation by setting up an agentic loop, under Cache Components / PPR, on initial load (hard navigation) and client-side navigation (soft navigation). Encode the goal as a failing @next/playwright instant() e2e and work it to green, one verified route at a time; the shipped test then…

vercel/next.js · 170 tokens

next-partial-prefetching-adoption

Turn on Partial Prefetching in a Next.js app and work through the insights it surfaces. Use when the user wants to enable or adopt Partial Prefetching, flip the partialPrefetching flag, opt routes in with export const prefetch = 'partial', audit Link prefetch={true} behavior, preserve existing prefetched UI with…

vercel/next.js · 103 tokens

chronicle

Analyze Copilot session history for standup reports, usage tips, session search, and session reindexing. Use when the user asks for a standup, daily summary, usage tips, workflow recommendations, wants to search or find past sessions by keyword/file/PR, wants to reindex their session store, or asks about deleting…

microsoft/vscode · 72 tokens