spec-design

name	spec-design
description	Guides interactive module design via Q&A before writing. Use when the user wants to design a module, class, or feature together, or when they say "/spec-design".

Spec Design

Guides a collaborative, question-first design process. Do not write design docs until ambiguities are clarified.

Process

Phase 1: Clarify First (Required)

Always start with clarifying questions. Do not propose a design or write a doc until the user answers.

Read relevant code (e.g. docs/overview.md, related src/ modules, config) to ground your questions. Then ask questions in categories below.

Phase 2: Question Categories

Ask 1–2 questions per category as needed. Adapt to context; not all apply.

Category	Examples
Path / terminology	"You said directory—do you mean file? resolveX() returns a file path."
Data flow	"Where does X come from—caller, config, or generated internally?"
Responsibilities	"Is this a factory, a repository, or both? What does it own vs delegate?"
Semantics	"Does 'resume' mean load history into context, or just set a flag?"
Concurrency	"Same ID—allow multiple instances? Do we need caching?"
Error handling	"File missing on resume—throw or return Result? Overwrite on create?"
Injection	"Config via constructor injection or direct import?"

If something contradicts existing code or docs, ask immediately.

Phase 3: Iterate

• Answer user answers; refine or add questions if needed
• Proceed to writing only when the design is clear enough to implement

Phase 4: Produce

• Write design doc to docs/designs/{module-name}.md
• Naming: Use kebab-case from class/module name (e.g. SessionManager → session-manager.md)
• Language: English only
• Style: Concise. No filler. Bullets and short sentences.

Output Format

Design doc structure (adjust as needed):

# {ModuleName} Design

One-line summary.

## Dependencies
- Imports, paths, config

## API
- Method signatures and behavior

## Error Handling
- When to throw, no graceful fallback

## Concurrency / Constraints
- Single-writer, no cache, etc.

Anti-Patterns

• Rushing to write: Asking questions and writing in the same turn
• Assuming: Filling gaps without asking (e.g. "目录" vs "文件")
• Over-specifying: Adding details the user did not confirm
• Chinese in design doc: Keep design docs in English