# Principle Subtract Before You Add

> Requires removal before addition. Apply when sequencing an addition, refactor, or rewrite of code, prompts, or skills.

- Skill: `bostonaholic/principle-subtract-before-you-add` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds@latest add bostonaholic/principle-subtract-before-you-add`
- Raw SKILL.md: https://api.skillmd.com/api/skills/bostonaholic/principle-subtract-before-you-add/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- Author: bostonaholic (https://skillmd.com/u/bostonaholic)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/bostonaholic/principle-subtract-before-you-add

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# Subtract Before You Add

Remove complexity first, then build on the simpler base; leave the design simpler behind the same or a smaller surface than you found it.

Why: Adding to a complex system compounds complexity; removing first shrinks the surface and usually makes the next design obvious.

- Sequence removal before construction: delete what the change replaces or leaves unused, then add.
- Cut before you polish: reach the minimum that satisfies the spec before investing in quality.
- Design for observed usage; add no validator, parser, guard, or option beyond what the design, plan, or tests demand.
- Treat an out-of-spec feature as dragging its own guards behind it; leave it out and record it as a finding.
- Simplify prompts and skills the same way: remove redundant instructions and templates, and delete a reference with no novel content instead of keeping a stub.
- Keep removals inside the approved scope under `principle-scope-fence`; record a wider removal as an opportunity, never perform it unasked.