# 📐 L2 Spec — Chemical Exchange Saturation Transfer (CEST) MRI Mismatch-Only Spec
**ID:** `L2-056-001` · **Status:** ⊙ Testnet (genesis catalog)
**Parents:** ⬆ Principle [`L1-056`](/artifact/l1/L1-056)
> **🎯 Tolerance (ε):** expression
> **⚖ Difficulty score:** 0.5 · **Delta tier:** 5
> **⛓ On-chain block:** 41553389
---
## 1. Domain Ω
**Type:** `range`
| Parameter | Unit | Range |
|---|---|---|
| H | px | 32 |
| W | px | 32 |
| Z | — | 4 – 64 |
| B1 ut | — | 0.5 – 5.0 |
| Tr ms | ms | 1000 – 10000 |
| Snr db | dB | 0.0 – 35.0 |
| N offsets | — | 10 – 101 |
| B0 inhomogeneity | — | 0.0 – 0.3 |
| B1 inhomogeneity | — | 0.0 – 0.3 |
| Mt contamination | — | 0.0 – 0.3 |
| Direct water saturation | — | 0.0 – 0.3 |
## 2. Tolerance (ε)
**Type:** `fn`
```
8.0 + 0.3 * SNR_dB - 10.0 * B0_inhomogeneity - 8.0 * B1_inhomogeneity - 8.0 * direct_water_saturation
```
## 3. Difficulty
| Property | Value |
|---|---|
| Difficulty score | 0.5 |
| Delta tier | 5 |
## 4. Fingerprint
`7d3500f5845c25e74760cf1ccabdeee7e75a510b48047042733be6065f2e5a22`
## 5. On-chain Registration
- **Chain hash:** `0x6b83697ae6a468d3fdd148bd8fb9940e2f81dd759ac32ef926b72b4a0c133dc0`
- **Chain tx hash:** `0x6b4009c9df135f24d8ae934cddb096437c81945d0e35eb906e6cb236e7f87424`
- **Chain block:** `41553389`
---
## File Mapping
This bundle consists of: `L2-056-001.md`, `L2-056-001.json`.
| File | Role | How to regenerate |
|------|------|-------------------|
| `L2-056-001.md` | Source of truth — edit this | Human or LLM |
| `L2-056-001.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 `L2-056-001`._
_Edit it, regenerate the JSON, and submit at [/submit](/submit) to claim the artifact._