# 📐  L2 Spec — Drug-Target Binding Affinity Classification (PWDR) — Spec Skeleton

**ID:** `L2-521-001` · **Status:** ⊙ Testnet (genesis catalog)
**Parents:** ⬆ Principle [`L1-521`](/artifact/l1/L1-521)

> **🎯 Tolerance (ε):** expression
> **⚖ Difficulty score:** 0.5 · **Delta tier:** 5
> **⛓ On-chain block:** 41554145

---

## 1. Domain Ω

**Type:** `range`

| Parameter | Unit | Range |
|---|---|---|
| Force field | — | [NEEDS_HAND_AUTHORING: bounds] |
| Water model | — | [NEEDS_HAND_AUTHORING: bounds] |
| N atoms drug | — | 10 – 200 |
| Temperature k | — | 273 – 320 |
| N atoms target | — | 500 – 50000 |
| Simulation time ns | ns | 1 – 10000 |
| Salt concentration m | m | [NEEDS_HAND_AUTHORING: bounds] |
| Drug protonation state | — | [NEEDS_HAND_AUTHORING: bounds] |
| Force field uncertainty | — | [NEEDS_HAND_AUTHORING: bounds] |
| Water model uncertainty | — | [NEEDS_HAND_AUTHORING: bounds] |
| Sampling convergence error | — | [NEEDS_HAND_AUTHORING: bounds] |
| Protein flexibility truncation | — | [NEEDS_HAND_AUTHORING: bounds] |
| Conformational search incompleteness | — | [NEEDS_HAND_AUTHORING: bounds] |

## 2. Tolerance (ε)

**Type:** `fn`

```
0.70_accuracy
```

## 3. Difficulty

| Property | Value |
|---|---|
| Difficulty score | 0.5 |
| Delta tier | 5 |

## 4. Fingerprint

`e67bbf901bab99b87f25a89918d0fd3a8cd68bbbe238b8980c3518e3262c8b86`

## 5. On-chain Registration

- **Chain hash:** `0xa04e7c27f47325fd8bf96163e351ee496891bcb7780571772e36adde4418dfa0`
- **Chain tx hash:** `0x915376c3550e3b5f78b5ad240eb804184106da61c5a8f1de791fc5ba1404db2e`
- **Chain block:** `41554145`

---

## File Mapping

This bundle consists of: `L2-521-001.md`, `L2-521-001.json`.

| File | Role | How to regenerate |
|------|------|-------------------|
| `L2-521-001.md` | Source of truth — edit this | Human or LLM |
| `L2-521-001.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 `L2-521-001`._
_Edit it, regenerate the JSON, and submit at [/submit](/submit) to claim the artifact._