{"slug":"domain-modeling-3","title":"domain-modeling","summary":"Build and sharpen a project's domain model. Use when discussing codebase terminology, writing or editing a CONTEXT.md, or recording or editing an ADR.","platform":"Claude","tags":[],"authorName":"LLM Mart","authorSlug":"llm-mart","score":0,"source":"github","price":null,"verified":false,"createdAt":"2026-09-17T16:53:07.923738Z","repo":{"url":"https://github.com/KongFangXun/sofagent","stars":49,"forks":9,"license":"MIT","updatedAt":"2026-09-24T19:13:19Z"},"bodyHtml":"
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name: domain-modeling\ndescription: Build and sharpen a project's domain model. Use when discussing codebase terminology, writing or editing a CONTEXT.md, or recording or editing an ADR.

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Domain Modeling

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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.)

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File structure

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Most repos have a single context:

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/\n├── CONTEXT.md\n├── docs/\n│   └── adr/\n│       ├── 0001-event-sourced-orders.md\n│       └── 0002-postgres-for-write-model.md\n└── src/\n
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If a CONTEXT-MAP.md exists at the root, the repo has multiple contexts. The map points to where each one lives:

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

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During the session

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Challenge against the glossary

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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?\"

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Sharpen fuzzy language

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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.\"

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Discuss concrete scenarios

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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.

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Cross-reference with code

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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?\"

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Update CONTEXT.md inline

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When a term is resolved, update CONTEXT.md right there. Don't batch these up: capture them as they happen. Use the format in CONTEXT-FORMAT.md.

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CONTEXT.md should be totally devoid of implementation details. Do not treat CONTEXT.md as a spec, a scratch pad, or a repository for implementation decisions. It is a glossary and nothing else.

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Offer ADRs sparingly

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Only offer to create an ADR when all three are true:

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  1. Hard to reverse: the cost of changing your mind later is meaningful
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  2. Surprising without context: a future reader will wonder \"why did they do it this way?\"
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  3. The result of a real trade-off: there were genuine alternatives and you picked one for specific reasons
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If any of the three is missing, skip the ADR. Use the format in ADR-FORMAT.md.

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