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principle-subtract-before-you-add SKILL.md skillA

principle-subtract-before-you-add from painhardcore/pstack is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.

Install it, pinned

mdr add painhardcore/pstack/principle-subtract-before-you-add@git:20260827.04830a9

Pins git:20260827.04830a9 in mdr.lock. Pin the fingerprint instead.

Audit grade: A, 17 of 17 checks passed
Kind: SKILL.md skill
Repository: painhardcore/pstack
Path: .opencode/skills/principle-subtract-before-you-add/SKILL.md
Versions recorded: 1
Latest version: git:20260827.04830a9, committed Aug 27, 2026
Size: 1,306 bytes
Repository stars: 12
License: MIT

Apply when sequencing an addition, refactor, or rewrite. Remove dead weight, redundant validators, and stub references first, then build on the simpler base.

Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.

What the file says

# Subtract Before You Add

When evolving a system, remove complexity first, then build. Deletion gives you a simpler base, which makes the next addition smaller and less brittle.

**Why:** Adding to a complex system compounds complexity. Removing first cuts the surface area, reveals the essential structure, and usually makes the next design obvious. Default to subtraction.

Make simplification a continual investment. Leave the design slightly simpler and more capable behind the same or smaller surface than you found it.

**The pattern:**
- Sequence removal before construction
- Cut before you polish (get to the minimum before investing in quality)
- Design for observed usage, not speculative edge cases
- No speculative validators, parsers, or guards beyond what the spec demands
- Out-of-spec features drag validators behind them. Persistence, retry-on-startup, and schema migration each need guards to defend their inputs.
- Simplify prompts (remove redundant instructions, excessive templates)
- When a reference has no novel content, delete it rather than leaving a stub

Read the whole file at its exact version.

How to install

The exact contents, by fingerprint

mdr add painhardcore/pstack/principle-subtract-before-you-add@sha256:6382fdd1225c9564

The line at the top of this page pins the label git:20260827.04830a9, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.

Badge

[![mdr](https://markdownregistry.com/badge/art_nfbzygbaivpnzfdj.svg)](https://markdownregistry.com/a/art_nfbzygbaivpnzfdj)

1 badge image fetches in 30 days. What the badge shows.

Versions

The registry has recorded 1 version of this file, committed on Aug 27, 2026.

version	committed	commit	size	audit
git:20260827.04830a9 latest	2026-08-27	04830a9	1,306 B	A	view

Audit of the latest version

A 17 of 17 checks passed. Fixed automatic checks with no AI involved, so the same checks give the same answer every run.

pass: Frontmatter block present
pass: Frontmatter declares a name
pass: Frontmatter declares a description
pass: Size between 200 bytes and 200 KB (1306 bytes)
pass: No zero-width or bidi control characters
pass: No instruction hidden inside an HTML comment
pass: No link to an exfiltration or paste host
pass: No credential-shaped string
pass: No instruction to send local credentials anywhere
pass: No text hidden with inline styles
pass: No prompt-injection phrasing
pass: No curl or wget piped into a shell
pass: No recursive delete of root, home or parent
pass: No instruction to read or print local credentials
pass: No base64 blob over 200 characters
pass: No link to a raw IP address
pass: No script tag

Source

GitHub

painhardcore/pstack · 12 stars · license MIT · pushed 2026-10-16 · branch master

API

GET https://markdownregistry.com/api/v1/artifacts/art_nfbzygbaivpnzfdj
GET https://markdownregistry.com/api/v1/resolve?ref=painhardcore/pstack/principle-subtract-before-you-add
GET https://markdownregistry.com/api/v1/blob/6382fdd1225c9564f3edd6c27aa112a7dae190992673ba3a7f00c58cec284254

Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.

Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.

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