new-spec-usecase

name

new-spec-usecase

description

Create the usecase layer spec template at `docs/spec/<feature>/usecase.md`. Asks for feature name (kebab-case) + usecase package name (lowercase, e.g., `user`) + Usecase interface name (default `Usecase`) via `AskUserQuestion`, reads the section structure for the usecase layer from `.claude/scaffold-spec/usecase-spec.md`, then writes a Markdown file with YAML code-block placeholders and TODO markers (Overview / Interface / DTOs / Dependencies / Workflow). NEVER overwrites an existing file. Does not invent business content — gathers identity only. Reads the spec format file at runtime so format changes propagate automatically.

New Spec — Usecase

Create the usecase layer spec template for one feature.

A Japanese reference translation of this skill is available at SKILL.ja.md in the same directory (not loaded as a skill; for human reference only).

When to Use

• Starting a new feature and need the usecase layer spec template.
• Adding the usecase spec to an existing feature directory.

Do NOT use this skill for:

• Editing an existing usecase.md — open in the editor directly.
• Generating Go code from spec — that's scaffold-usecase.
• Validating spec consistency — that's verify-spec.
• Creating both layer specs (domain + usecase) in one go — use the integrator new-spec. lean A only requires these two specs; controller / infra are derived from OpenAPI gen + sqlc gen, no spec file.

What This Skill Reads / Writes

Reads (always):

• .claude/scaffold-spec/usecase-spec.md — canonical section list for the usecase layer.
• docs/spec/<feature>/ — checks whether usecase.md already exists.

Writes (with confirmation):

• docs/spec/<feature>/usecase.md — template file.

Never touches:

• Existing usecase.md (aborts if found).
• Any other layer's spec file.

First Step: Confirm Identity

This skill MUST call AskUserQuestion immediately after invocation (unless invoked from new-spec integrator with the feature name in context):

1. Feature name — free-text, kebab-case. Validate ^[a-z][a-z0-9-]*$.
2. Usecase package name — free-text, lowercase (e.g., user, order).
3. Usecase interface name — free-text, default Usecase (PascalCase).

If docs/spec/<feature>/usecase.md exists → abort. Otherwise create docs/spec/<feature>/ if missing.

Step 1. Read Section Definitions

Read .claude/scaffold-spec/usecase-spec.md for the canonical section list:

1. Overview
2. Interface
3. DTOs
4. Dependencies
5. Workflow

NEVER hardcode — re-read the spec format file each run.

Step 2. Generate the Template

Assemble Markdown with H1 title <FeatureName Display> — Usecase Spec, then per section:

• Overview: single TODO: line
• Interface: YAML code block with package / name / methods (1 placeholder method)
• DTOs: YAML code block with placeholder DTO struct
• Dependencies: YAML code block with placeholder boundary list
• Workflow: H3 per method with YAML block (tx_required / steps / calls / errors)

Use the example output shown in .claude/scaffold-spec/usecase-spec.md as the literal template format.

Step 3. Confirm and Write

Display proposed path + first ~20 lines, then ask:

• 「以下の内容で docs/spec/<feature>/usecase.md を作成しますか？」
• Options: 「作成する」 / 「キャンセル」

If approved, mkdir -p docs/spec/<feature> and Write the file.

Step 4. Closing

docs/spec/<feature>/usecase.md を作成しました。次は editor で TODO を埋めてください。
domain spec も必要なら new-spec-domain または統合 new-spec を使ってください
（lean A 構成: controller / infra spec は不要、OpenAPI gen + sqlc gen から導出されます）。

AI Modification Scope

• Write scope: new files under docs/spec/<feature>/ only.
• Aborts if usecase.md exists.

Constraints

• ❌ Overwrite an existing usecase.md
• ❌ Invent business content (methods / DTOs / workflow)
• ❌ Hardcode section list (always read .claude/scaffold-spec/usecase-spec.md)
• ❌ Skip the identity AskUserQuestion
• ❌ Touch any layer other than usecase.md
• ✅ Japanese user-facing output
• ✅ Validate feature name kebab-case + package name lowercase

Checklist

• Feature + package + interface name confirmed via AskUserQuestion
• .claude/scaffold-spec/usecase-spec.md read for current section list
• usecase.md did NOT already exist (skill aborts otherwise)
• Template written with H2 sections + YAML codeblocks + TODO markers
• Final summary in Japanese
• Only docs/spec/<feature>/usecase.md was written