# 📐 L2 Spec — Cohesive Zone Model — traction-separation interface Mismatch-Only Spec
**ID:** `L2-221-001` · **Status:** ⊙ Testnet (genesis catalog)
**Parents:** ⬆ Principle [`L1-221`](/artifact/l1/L1-221)
> **🎯 Tolerance (ε):** expression
> **⚖ Difficulty score:** 0.48 · **Delta tier:** 5
> **⛓ On-chain block:** 41554015
---
## 1. Domain Ω
**Type:** `range`
| Parameter | Unit | Range |
|---|---|---|
| N dof | — | 100 – 1000000 |
| N inc | — | 10 – 10000 |
| Snr db | dB | 0 – 40 |
| G c error | — | 0.0 – 0.2 |
| Delta 0 error | — | 0.0 – 0.2 |
| Sigma max error | — | 0.0 – 0.2 |
## 2. Tolerance (ε)
**Type:** `fn`
```
15.0 + 0.3*SNR_dB - 15.0*sigma_max_error - 20.0*G_c_error - 10.0*delta_0_error
```
## 3. Difficulty
| Property | Value |
|---|---|
| Difficulty score | 0.48 |
| Delta tier | 5 |
## 4. Fingerprint
`7c0355f60cbacf88c80557e75325bb6687e3c4dece0929ab076840c792dfaf10`
## 5. On-chain Registration
- **Chain hash:** `0x611da0e93a3ff01bc45e0a26029b2d90b7a739803d5cde41b1a0eee5cea95403`
- **Chain tx hash:** `0xb867c1f2a990a5d6e9ced3b2774f5549922209323b11a17360f8cb6ef79ffee1`
- **Chain block:** `41554015`
---
## File Mapping
This bundle consists of: `L2-221-001.md`, `L2-221-001.json`.
| File | Role | How to regenerate |
|------|------|-------------------|
| `L2-221-001.md` | Source of truth — edit this | Human or LLM |
| `L2-221-001.json` | Structured metadata for the registry | LLM regenerates from the sections above |
**Prompt for your LLM after editing this Markdown:**
> Read the attached Markdown. Regenerate the sibling `.json` so every field matches.
> Preserve the schema documented in the rows above.
> Output each file in its own fenced code block tagged with the filename.
> Output only the JSON object.
_This Markdown was auto-synthesized from the catalog row for `L2-221-001`._
_Edit it, regenerate the JSON, and submit at [/submit](/submit) to claim the artifact._