Domain Modeling

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     variant added; cc10x frontmatter). Companions (CONTEXT-FORMAT.md, ADR-FORMAT.md)
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Domain Modeling

Actively build and sharpen the project's domain model as you design. This is the active discipline — challenging terms, inventing edge-case scenarios, and writing the glossary and decisions down the moment they crystallise. (Merely reading CONTEXT.md for vocabulary is not this skill — that's a one-line habit any skill can do. This skill is for when you're changing the model, not just consuming it.)

Active vs read-only

This skill loads in two modes depending on which agent invoked it:

• ACTIVE (planner, doc-syncer, exploration in DESIGN mode): you shape the domain model. You challenge terms, sharpen language, write CONTEXT.md inline, and offer ADRs. You are a designated CONTEXT.md writer.
• READ-ONLY / OBEY (component-builder, bug-investigator): you read CONTEXT.md and use the project's domain vocabulary in all output. You do NOT write or edit CONTEXT.md. If you discover a contradiction between the glossary and the code, emit a proposal in your Memory Notes (**Domain proposal:** term X is defined as Y in CONTEXT.md but the code does Z — which is right?) or block (STATUS: FAIL, REMEDIATION_REASON: "Domain glossary contradicts code at term X") — do NOT resolve the contradiction yourself. Resolving domain language is the job of shaping phases, not build phases.

The agent's persona prompt determines which mode is in effect. If unsure, default to READ-ONLY — the cost of an opportunistic glossary rewrite during a build is higher than the cost of a deferred proposal.

Autonomous transform (how human-gates route here)

Matt's original skill is human-gated ("ask the user", "challenge the user"). In cc10x's autonomous workflow, every gate routes through evidence + blast radius, not reversibility alone:

Grilling is NOT auto-answered. Auto-answering an interview removes its information source. In JUST_GO mode, the exploration interview asks questions, records the recommended answer + assumption, and proceeds ONLY for low-blast-radius decisions. Domain-shaping questions always stop for human input.

File structure

Most repos have a single context:

/
├── CONTEXT.md
├── docs/
│   └── adr/
│       ├── 0001-event-sourced-orders.md
│       └── 0002-postgres-for-write-model.md
└── src/

If a CONTEXT-MAP.md exists at the root, the repo has multiple contexts. The map points to where each one lives:

/
├── CONTEXT-MAP.md
├── docs/
│   └── adr/                          ← system-wide decisions
├── src/
│   ├── ordering/
│   │   ├── CONTEXT.md
│   │   └── docs/adr/                 ← context-specific decisions
│   └── billing/
│       ├── CONTEXT.md
│       └── docs/adr/

Create files lazily — only when you have something to write. If no CONTEXT.md exists, create one when the first term is resolved. If no docs/adr/ exists, create it when the first ADR is needed.

During the session (ACTIVE mode)

Challenge against the glossary

When the user uses a term that conflicts with the existing language in CONTEXT.md, call it out immediately. "Your glossary defines 'cancellation' as X, but you seem to mean Y — which is it?" In autonomous mode, if the contradiction affects contracts/persistence/user-language, STOP per the transform table; otherwise surface it and proceed with the sharpened term.