Feature Dev Skill for Claude

Feature Development Workflow

A comprehensive, structured workflow for feature development with specialized agents for codebase exploration, architecture design, and quality review.

Quick Start

Launch the guided feature development workflow:

/feature-dev Add user authentication with OAuth

Or interactively:

/feature-dev

The workflow will guide you through 7 distinct phases automatically.

Overview

Building features requires more than just writing code. This skill provides a systematic approach that:

• Understands the codebase before making changes
• Asks clarifying questions to resolve ambiguities
• Designs thoughtfully with multiple architecture options
• Reviews for quality after implementation

The 7-Phase Workflow

Phase 1: Discovery

Goal: Understand what needs to be built

• Clarifies unclear feature requests
• Identifies problem, constraints, and requirements
• Summarizes understanding and confirms with user

Example:

User: /feature-dev Add caching
Agent: Let me understand what you need...
       - What should be cached? (API responses, computed values, etc.)
       - What are your performance requirements?
       - Do you have a preferred caching solution?

Phase 2: Codebase Exploration

Goal: Understand relevant existing code and patterns

• Launches 2-3 code-explorer agents in parallel
• Explores similar features, architecture, UI patterns
• Reads all identified files for deep understanding
• Presents comprehensive summary of findings

Agents launched:

• "Find features similar to [feature] and trace implementation"
• "Map the architecture and abstractions for [area]"
• "Analyze current implementation of [related feature]"

Example output:

Found similar features:
- User authentication (src/auth/): Uses JWT tokens, middleware pattern
- Session management (src/session/): Redis-backed, 24hr expiry

Key files:
- src/auth/AuthService.ts:45 - Core authentication logic
- src/middleware/authMiddleware.ts:12 - Request authentication

Phase 3: Clarifying Questions

Goal: Fill in gaps and resolve all ambiguities

• Reviews codebase findings and feature request
• Identifies underspecified aspects (edge cases, error handling, integration points)
• Presents organized list of questions
• Waits for answers before proceeding

Example:

Before designing, I need to clarify:

1. OAuth provider: Which providers? (Google, GitHub, custom?)
2. User data: Store OAuth tokens or just profile?
3. Existing auth: Replace or add alongside current auth?
4. Sessions: Integrate with existing session management?
5. Error handling: How to handle OAuth failures?

Critical: Ensures nothing is ambiguous before design begins.

Phase 4: Architecture Design

Goal: Design multiple implementation approaches

• Launches 2-3 code-architect agents with different focuses:
• Minimal changes: Smallest change, maximum reuse
• Clean architecture: Maintainability, elegant abstractions
• Pragmatic balance: Speed + quality
• Presents comparison with trade-offs and recommendation
• Asks which approach to use

Example output:

Approach 1: Minimal Changes
- Extend existing AuthService with OAuth methods
Pros: Fast, low risk
Cons: Couples OAuth to existing auth

Approach 2: Clean Architecture
- New OAuthService with dedicated interface
Pros: Clean separation, testable
Cons: More files, more refactoring

Approach 3: Pragmatic Balance
- New OAuthProvider abstraction
Pros: Balanced complexity and cleanliness
Cons: Some coupling remains

Recommendation: Approach 3 - clean boundaries without excessive refactoring

Phase 5: Implementation

Goal: Build the feature

• Waits for explicit approval before starting
• Reads all relevant files from previous phases
• Implements following chosen architecture
• Follows codebase conventions strictly
• Updates todos to track progress

Phase 6: Quality Review

Goal: Ensure code is simple, DRY, elegant, and functionally correct

• Launches 3 code-reviewer agents in parallel:
• Simplicity/DRY/Elegance: Code quality
• Bugs/Correctness: Functional correctness
• Conventions/Abstractions: Project standards
• Consolidates findings and identifies high severity issues
• Asks what to do: Fix now, fix later, or proceed as-is

Example output:

High Priority Issues:
1. Missing error handling in OAuth callback (src/auth/oauth.ts:67)
2. Memory leak: OAuth state not cleaned up (src/auth/oauth.ts:89)

Medium Priority:
1. Could simplify token refresh logic (src/auth/oauth.ts:120)

What would you like to do?

Phase 7: Summary

Goal: Document what was accomplished

• Marks all todos complete
• Summarizes what was built, key decisions, files modified
• Suggests next steps

Specialized Agents

code-explorer

Purpose: Deeply analyzes existing codebase features by tracing execution paths

Focus:

• Entry points and call chains
• Data flow and transformations
• Architecture layers and patterns
• Implementation details

Output:

• Entry points with file:line references
• Step-by-step execution flow
• Key components and responsibilities
• Essential files to read

Triggered: Automatically in Phase 2, or manually

code-architect

Purpose: Designs feature architectures and implementation blueprints

Focus:

• Codebase pattern analysis
• Architecture decisions
• Component design
• Implementation roadmap

Output:

• Patterns and conventions found
• Architecture decision with rationale
• Complete component design
• Implementation map with build sequence

Triggered: Automatically in Phase 4, or manually

code-reviewer

Purpose: Reviews code for bugs, quality issues, and project conventions

Focus:

• Project guideline compliance (CLAUDE.md)
• Bug detection
• Code quality issues
• Confidence-based filtering (≥80% confidence only)

Output:

• Critical issues (confidence 75-100)
• Important issues (confidence 50-74)
• Specific fixes with file:line references

Triggered: Automatically in Phase 6, or manually

Usage Patterns

Full workflow (recommended for new features)

/feature-dev Add rate limiting to API endpoints

Manual agent invocation

Explore a feature:

"Launch code-explorer to trace how authentication works"

Design architecture:

"Launch code-architect to design the caching layer"

Review code:

"Launch code-reviewer to check my recent changes"

When to Use

Use for:

• New features that touch multiple files
• Features requiring architectural decisions
• Complex integrations with existing code
• Features where requirements are somewhat unclear

Don't use for:

• Single-line bug fixes
• Trivial changes
• Well-defined simple tasks
• Urgent hotfixes

Best Practices

• Use the full workflow for complex features: The 7 phases ensure thorough planning
• Answer clarifying questions thoughtfully: Phase 3 prevents future confusion
• Choose architecture deliberately: Phase 4 gives options for a reason
• Don't skip code review: Phase 6 catches issues before production
• Read the suggested files: Phase 2 identifies key files—read them for context

Common Issues

Agents take too long

Cause: Normal for large codebases

Solution: Agents run in parallel when possible. Thoroughness pays off in better understanding.

Too many clarifying questions

Cause: Feature request too vague

Solution: Be more specific in initial request. Provide context about constraints upfront.

Architecture options overwhelming

Cause: Multiple valid approaches presented

Solution: Trust the recommendation (based on codebase analysis). Pick pragmatic option when in doubt.

Requirements

• Claude Code installed
• Git repository (for code review)
• Existing codebase (workflow learns from existing patterns)

Tips

• Be specific in feature request: More detail = fewer clarifying questions
• Trust the process: Each phase builds on the previous one
• Review agent outputs: Agents provide valuable codebase insights
• Don't skip phases: Each phase serves a purpose
• Use for learning: Exploration phase teaches you about your own codebase

Verification Checklist

After using the workflow:

• [ ] All 7 phases completed successfully
• [ ] Clarifying questions answered in Phase 3
• [ ] Architecture approach selected in Phase 4
• [ ] Implementation approved before Phase 5 started
• [ ] Code review findings addressed in Phase 6
• [ ] Summary generated with next steps in Phase 7
• [ ] Feature works as expected
• [ ] Code follows project conventions

References

For detailed workflow documentation, see README.md

For agent specifications, see:

• agents/code-explorer.md
• agents/code-architect.md
• agents/code-reviewer.md

For slash command implementation, see commands/feature-dev.md