domain-modeling · diff
git:20260831.64fb3ee to git:20261005.870ecad
12 added, 12 removed. Audit A to A.
---
name: domain-modeling
- description: "Build and sharpen a project's domain model: challenge terms against the glossary, resolve fuzzy language, stress-test concepts with concrete scenarios, and record CONTEXT.md entries and ADRs the moment decisions land. Use when pinning down domain terminology or a ubiquitous language, recording an architectural decision, or when another skill (grilling, wayfinder, to-spec) needs the domain model maintained."
+ description: "Build and sharpen a project's domain model: challenge terms against the glossary, resolve fuzzy language, stress-test concepts with concrete scenarios, and record GLOSSARY.md entries and ADRs the moment decisions land. Use when pinning down domain terminology or a ubiquitous language, recording an architectural decision, or when another skill (grilling, wayfinder, to-spec) needs the domain model maintained."
---
# 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.
+ 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* `GLOSSARY.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.
Runs alongside `grilling` sessions (`grill-with-docs` is the front door that pairs the two), `wayfinder` grilling tickets, and `to-spec` synthesis: anywhere terms get decided. It's supporting work, not a pipeline stage: it never prints the pipeline end-of-session block, whether nested or run directly, the invoking skill (or the user's next step) owns routing.
## File structure
Most repos have a single context:
```
/
- ├── CONTEXT.md
+ ├── GLOSSARY.md
├── docs/
│ └── adr/
│ ├── 0001-single-db-multi-tenancy.md
│ └── 0002-money-as-integer-minor-units.md
└── app/
```
- If a `CONTEXT-MAP.md` exists at the root, the repo has multiple contexts. The map points to where each one lives: in a Laravel modular monolith that's the module root:
+ If a `GLOSSARY-MAP.md` exists at the root, the repo has multiple contexts. The map points to where each one lives: in a Laravel modular monolith that's the module root:
```
/
- ├── CONTEXT-MAP.md
+ ├── GLOSSARY-MAP.md
├── docs/
│ └── adr/ ← system-wide decisions
└── app/Domain/ ← or modules/, app-modules/, follow the repo
├── Ordering/
- │ ├── CONTEXT.md
+ │ ├── GLOSSARY.md
│ └── docs/adr/ ← context-specific decisions
└── Billing/
- ├── CONTEXT.md
+ ├── GLOSSARY.md
└── docs/adr/
```
- Create files lazily: only when you have something to write. No `CONTEXT.md`? Create one when the first term is resolved. No `docs/adr/`? Create it when the first ADR is needed. Formats: [references/context-format.md](references/context-format.md) and [references/adr-format.md](references/adr-format.md).
+ Create files lazily: only when you have something to write. No `GLOSSARY.md`? Create one when the first term is resolved. Found the old `CONTEXT.md` / `CONTEXT-MAP.md` instead? Before the first write, `git mv` it to `GLOSSARY.md` / `GLOSSARY-MAP.md` and fix the map's links. No `docs/adr/`? Create it when the first ADR is needed. Formats: [references/glossary-format.md](references/glossary-format.md) and [references/adr-format.md](references/adr-format.md).
## During the session
### 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?"
+ When the user uses a term that conflicts with the existing language in `GLOSSARY.md`, call it out immediately: "Your 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. Where `AskUserQuestion` is available, put the candidates as options: your recommendation first, each option's description saying what choosing it commits the model to; otherwise ask the same shape in chat. "You're saying 'account', is that the Customer or the User?" is a click-to-answer decision, not an open-ended essay prompt.
### Discuss concrete scenarios
When domain relationships are being discussed, stress-test them with specific scenarios. Invent scenarios that probe edge cases and force precision about the boundaries between concepts: "A Customer with two Subscriptions cancels one mid-cycle, what happens to the Invoice already issued?"
### Cross-reference with code
When the user states how something works, check whether the code agrees. In a Laravel codebase the model lives in more places than prose, check the glossary term against:
- Eloquent model and relationship names (`app/Models`, `HasMany` method names)
- Table and column names in migrations
- Enum cases (`app/Enums`)
- Policy names and ability strings
- Filament resource/page labels and navigation names
- Route names, job names, event names
If you find a contradiction, surface it: "Your code cancels entire Orders (`Order::cancel()`), but you just said partial cancellation is possible, which is right?" When a term is resolved *against* the code's current naming, the rename is real **build** work, record the *decision* here, and leave the rename itself for the spec (or a `tickets/` ticket once one exists), never as a `wayfinder` decision-map ticket, which holds only things decided, not things built. Never silently absorb it.
- ### Update CONTEXT.md inline
+ ### Update GLOSSARY.md inline
- When a term is resolved, update `CONTEXT.md` right there. Don't batch these up: capture them as they happen. Use the format in [references/context-format.md](references/context-format.md). If sessions may run in parallel, re-read `CONTEXT.md` immediately before writing and add only your entry, so a concurrent edit isn't clobbered.
+ When a term is resolved, update `GLOSSARY.md` right there. Don't batch these up: capture them as they happen. Use the format in [references/glossary-format.md](references/glossary-format.md). If sessions may run in parallel, re-read `GLOSSARY.md` immediately before writing and add only your entry, so a concurrent edit isn't clobbered.
- `CONTEXT.md` must stay totally devoid of implementation details. It is a glossary, not a spec, a scratch pad, or a home for implementation decisions.
+ `GLOSSARY.md` must stay totally devoid of implementation details. It is a glossary, not a spec, a scratch pad, or a home for implementation decisions.
### Offer ADRs sparingly
Only offer to create an ADR 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, skip the ADR. Use the format in [references/adr-format.md](references/adr-format.md).