domain-modeling

name	domain-modeling
description	Build and sharpen a project's vault-backed domain model. Use when the user wants to pin down domain terminology, record a durable decision, or when another skill needs to maintain project language.

Domain Modeling

Actively build and sharpen the project's domain model as you design. Challenge terms, invent edge-case scenarios, and update vault context and decision artifacts the moment they crystallise. Reading existing vocabulary is ordinary context gathering; this skill is for changing the model.

Vault structure

Load /vault, then inspect the project's language with vlt context list, vlt context check, and vlt context show [name|map]. Context may be a single project glossary or a map of named contexts. Use vlt context set to create or replace terms; the CLI owns the underlying files.

Store durable trade-offs as typed vault artifacts:

vlt create --type decision --topic "<decision topic>" --json
vlt update <decision-stem> --stdin --json

Create context entries and decision artifacts lazily, only when something has resolved.

During the session

Challenge against the glossary

When the user uses a term that conflicts with vault context, call it out immediately. "The project glossary defines 'cancellation' as X, but you seem to mean Y — which is it?"

Sharpen fuzzy language

When the user uses vague or overloaded terms, propose a precise canonical term. "You're saying 'account' — do you mean the Customer or the User? Those are different things."

Discuss concrete scenarios

When domain relationships are being discussed, stress-test them with specific scenarios. Invent scenarios that probe edge cases and force the user to be precise about the boundaries between concepts.

Cross-reference with code

When the user states how something works, check whether the code agrees. If you find a contradiction, surface it: "Your code cancels entire Orders, but you just said partial cancellation is possible — which is right?"

Update vault context inline

When a term is resolved, run vlt context set <term> --definition "..." [--avoid "..."] [--context <name>] --json right there. Capture terms as they happen. Use CONTEXT-FORMAT.md for content guidance.

Keep vault context as a glossary: canonical vocabulary and tight definitions. Put behavior in specs and trade-offs in decision artifacts.

Offer decision artifacts sparingly

Only offer to create a decision artifact when all three are true:

1. Hard to reverse — the cost of changing your mind later is meaningful
2. Surprising without context — a future reader will wonder "why did they do it this way?"
3. The result of a real trade-off — there were genuine alternatives and you picked one for specific reasons

If any of the three is missing, leave the choice in the conversation or its owning spec. Use DECISION-FORMAT.md.