# 📐 L2 Spec — MALDI-MSI Mapping Spec (tissue lipid family)
**ID:** `L2-127-001` · **Status:** ⊙ Testnet (genesis catalog)
**Parents:** ⬆ Principle [`L1-127`](/artifact/l1/L1-127)
> **🎯 Tolerance (ε):** expression
> **⚖ Difficulty score:** 0.3 · **Delta tier:** 5
> **⛓ On-chain block:** 41554216
---
## 1. Domain Ω
**Type:** `range`
| Parameter | Unit | Range |
|---|---|---|
| H | px | 32 – 2048 |
| K | — | 1 – 50 |
| W | px | 32 – 2048 |
| N mz | — | 1000 – 200000 |
| R mass | — | 2000 – 500000 |
| Pixel um | µm | 5 – 200 |
| Ion suppression | — | 0.0 – 0.5 |
| Laser energy drift | — | 0.0 – 0.2 |
| Tissue heterogeneity | — | 0.0 – 0.3 |
| Mass calibration error | — | 0.0 – 50 |
| Matrix hot spot variability | — | 0.0 – 0.5 |
## 2. Tolerance (ε)
**Type:** `fn`
```
0.02 + 0.1 * matrix_hot_spot_variability + 0.1 * laser_energy_drift + 0.1 * ion_suppression + 5e-4 * mass_calibration_error
```
## 3. Difficulty
| Property | Value |
|---|---|
| Difficulty score | 0.3 |
| Delta tier | 5 |
## 4. Fingerprint
`cc53eb409f8c1fccce3f154e6c99b72622767cf1255ca8f43c73900901b53a02`
## 5. On-chain Registration
- **Chain hash:** `0xde2b05a9b446fecb29852aa8d80f34222a4e01989956364a599df35b76404415`
- **Chain tx hash:** `0xd1db071f28491cc9abf35db297a9bf0f181aa7d2a1606a3c5ba36ceae5008cff`
- **Chain block:** `41554216`
---
## File Mapping
This bundle consists of: `L2-127-001.md`, `L2-127-001.json`.
| File | Role | How to regenerate |
|------|------|-------------------|
| `L2-127-001.md` | Source of truth — edit this | Human or LLM |
| `L2-127-001.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 `L2-127-001`._
_Edit it, regenerate the JSON, and submit at [/submit](/submit) to claim the artifact._