# Ultra Compact

> Ultra-Compact JSON (P12)

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

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# Ultra-Compact JSON (P12)
Three compression levels: single-char keys, array format, delta-only.

**Trigger:** When generating JSON reports — always use the most compact format.

**Levels:**
1. Single-char keys: -30% vs standard compact
2. Array format (no keys): -38% vs compact
3. Delta-only (send changes): -90% for iterative reports

**Module:** `skills/ultra_compact`
**Functions:** to_ultra(), to_array(), delta_only(), compare_sizes()