# 📐 L2 Spec — Viscoelasticity — linear hereditary models Mismatch-Only Spec
**ID:** `L2-218-001` · **Status:** ⊙ Testnet (genesis catalog)
**Parents:** ⬆ Principle [`L1-218`](/artifact/l1/L1-218)
> **🎯 Tolerance (ε):** expression
> **⚖ Difficulty score:** 0.48 · **Delta tier:** 5
> **⛓ On-chain block:** 41554014
---
## 1. Domain Ω
**Type:** `range`
| Parameter | Unit | Range |
|---|---|---|
| Snr db | dB | 0 – 40 |
| N freqs | — | 5 – 500 |
| N modes | — | 1 – 50 |
| G prony error | — | 0.0 – 0.1 |
| Tau prony error | — | 0.0 – 0.2 |
| Wlf c1 c2 error | — | 0.0 – 0.3 |
## 2. Tolerance (ε)
**Type:** `fn`
```
19.0 + 0.3*SNR_dB - 30.0*G_prony_error - 15.0*tau_prony_error - 10.0*wlf_c1_c2_error
```
## 3. Difficulty
| Property | Value |
|---|---|
| Difficulty score | 0.48 |
| Delta tier | 5 |
## 4. Fingerprint
`e32d8ef453c8a0dab3a6c58ade610d73c6c27c278fbb9c621c3ef3b8afa7a7eb`
## 5. On-chain Registration
- **Chain hash:** `0x5b51b7da16b53f28699e7d0c7dd0d737979131a622f667989dba2129245859a4`
- **Chain tx hash:** `0x0dbaaa60aae26df9816ac7106a78a62c4d5eeaa5fdd06f4e0d07746fd41f66a5`
- **Chain block:** `41554014`
---
## File Mapping
This bundle consists of: `L2-218-001.md`, `L2-218-001.json`.
| File | Role | How to regenerate |
|------|------|-------------------|
| `L2-218-001.md` | Source of truth — edit this | Human or LLM |
| `L2-218-001.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 `L2-218-001`._
_Edit it, regenerate the JSON, and submit at [/submit](/submit) to claim the artifact._