rugged-gemini: Skill for Gemini CLI

Parallel Dispatch: File Ownership

Enforce exclusive write access per parallel sub-task. This is the safety invariant — if ownership is valid, merges are conflict-free by construction.

When to Invoke

• After scope cards are produced, before DAG dispatch
• At each merge point to verify no ownership violations occurred
• When re-decomposing after a failure

Ownership Model

Three Zones

Zone	Access	Who	Immutability
Exclusive Write	Read + Write	Exactly one sub-task	Mutable only by owner
Shared Read	Read only	Any sub-task	Immutable during BUILD phase
Contracts Layer	Read only	All BUILD agents	Produced by DESIGN phase, frozen for BUILD

Exclusive Write

Each writing sub-task owns a disjoint set of files or directories. No two writers may touch the same file. This is enforced at the glob-pattern level from scope cards.

Shared Read

Any sub-task can read files outside its write scope. Common shared reads:

• Type definitions and interfaces
• Configuration templates
• Middleware and utility packages
• Test helpers and fixtures

Shared read files MUST NOT be modified by any BUILD-phase sub-task. If a BUILD agent needs to modify a shared file, it must be assigned to exactly one sub-task's write scope or handled by an integration sub-task.

Contracts Layer

Files produced during DESIGN phase that define interfaces between features:

• API contracts (endpoint definitions, request/response types)
• Database schemas (table definitions, migration files)
• Shared type definitions

These are frozen during BUILD. If a BUILD agent discovers the contract needs changes → STOP and escalate to orchestrator for a DESIGN revision.

Ownership Matrix

Build a matrix from scope cards before dispatch. This is a dynamic output, not a static template. Actual paths come from the project's real structure discovered during decomposition.

## File Ownership Matrix

| Sub-Task | Write Scope (exclusive) | Shared Reads |
|----------|------------------------|--------------|
| @<agent>[<scope-1>] | `<path/to/feature-1>/**` | `<path/to/types>/**`, `<path/to/config>/**` |
| @<agent>[<scope-2>] | `<path/to/feature-2>/**` | `<path/to/types>/**`, `<path/to/config>/**` |
| @<agent>[integration] | `<path/to/router>/**`, `<path/to/main>.*` | All feature directories (read-only) |