Spec

SPEC-Based Development - Interview

SPEC-based development workflow from Anthropic engineer Thariq.

Triggers

• "spec", "specification", "interview", "feature design"

Workflow

Step 1: Check or Create SPEC.md

Check if SPEC.md exists in the current directory.

• If yes: Read it and start interview
• If no: Ask user for basic idea, then generate draft

Step 2: In-Depth Interview

Must use AskUserQuestion tool to ask questions in the following areas:

1. Technical Implementation

   • What tech stack to use
   • Integration method with existing codebase
   • Performance requirements

2. UI & UX

   • User flows
   • Design patterns
   • Accessibility requirements

3. Concerns

   • Security considerations
   • Scalability issues
   • Maintenance complexity

4. Trade-offs

   • Time vs quality
   • Simplicity vs functionality
   • Flexibility vs performance

Step 3: Question Rules

• No obvious questions: Skip clear ones like "what language?"
• Go deep: 40+ questions are fine
• Continuous interview: Keep asking until complete
• 1-2 questions at a time: Easy for user to answer

Step 4: Specification Writing

After interview completion, update SPEC.md file in detail:

# [Feature Name] Specification

## Overview
[One sentence description]

## Goals
- [ ] Goal 1
- [ ] Goal 2

## Tech Stack
- ...

## Detailed Requirements
### Functional Requirements
1. ...

### Non-Functional Requirements
1. ...

## UI/UX Specification
- ...

## API Design (if applicable)
- ...

## Data Model (if applicable)
- ...

## Security Considerations
- ...

## Test Plan
- ...

## Milestones
1. [ ] Phase 1
2. [ ] Phase 2

## Open Questions / Decisions Needed
- ...

Step 5: Guidance

After completing the specification, guide the user:

"The specification is complete. Start implementation in a new session with the following command:"

Read SPEC.md and start implementing

After implementation, verify:

/spec-verify

Core Principles

1. Context separation: Interview session != Implementation session
2. User control: User decides direction through questions
3. Detailed documentation: Sufficient detail for immediate execution in the next session