# E2.M1 — SkillDefinitionRegistry

## Summary

| Field | Value |
|--------|--------|
| **Module ID** | E2.M1 |
| **Epic** | [Epic 2 — Classless Progression](../epics/epic_02_classless_progression.md) |
| **Stage target** | Prototype |
| **Status** | Planned (see [dependency register](module_dependency_register.md)) |

## Purpose

Central catalog for skill metadata, category tags, and unlock prerequisites. All prototype activities reference skills by stable IDs validated against this registry.

## Responsibilities

- Load and validate `SkillDef` from data; expose `SkillCategory` and `UnlockRequirement` for gating.

## Key contracts

| Contract | Role |
|----------|------|
| `SkillDef` | Per-skill metadata and references. |
| `SkillCategory` | Grouping for UX and balance. |
| `UnlockRequirement` | Prerequisites before XP or use counts apply. |

## Module dependencies

- **None**

## Dependents (by design)

- **E2.M2** — XpAwardAndLevelEngine (primary).

## Related implementation slices

Epic 2 **Slice 1** — skill registry and prototype skills; invalid references fail at load or in CI.

## Source anchors

- Master plan: [`neon_sprawl_vision.plan.md`](../../../neon_sprawl_vision.plan.md) — Epic 2.
- [Module dependency register](module_dependency_register.md)