Agent Skills: Feature Implementation Workflow

Skill Variant: Use this skill for autonomous feature implementation with structured workflows. For interactive feature development with user feedback, use feature instead. For investigating existing features (READ-ONLY), use investigate.

Feature Implementation Workflow

Summary

Goal: Autonomously implement new features across all layers (Domain, Application, Persistence, API, Frontend) with investigation-first approach.

| Step | Action | Key Notes | |------|--------|-----------| | 1 | Discovery & analysis | Decompose requirements, investigate codebase, find similar patterns | | 2 | Impact analysis | Map changes per layer: Domain, Application, Persistence, API, Frontend | | 3 | Approval gate | Present plan to user before any implementation | | 4 | Implementation | Backend: Domain first, then Persistence, Application, API. Frontend: Service, Store, Components | | 5 | Verification | Compile, test endpoints, check authorization, error handling |

Key Principles:

• INVESTIGATE before implementing -- never assume, verify with code evidence
• Implement layers in order: Domain -> Persistence -> Application -> API -> Frontend
• Always request user approval at checkpoint gates before coding

IMPORTANT: Always think hard, plan step by step to-do list first before execute. Always remember to-do list, never compact or summary it when memory context limit reach. Always preserve and carry your to-do list through every operation.

Prerequisites: MUST READ .claude/skills/shared/anti-hallucination-protocol.md before executing.

Core Principles

• INVESTIGATE before implementing
• Follow established patterns in existing code
• Use External Memory for complex features
• Request user approval at checkpoint gates
• Never assume - verify with code evidence

Phase 1: Discovery & Analysis

Step 1.1: Requirement Decomposition

## Feature Analysis
- **Feature Name**: [Name]
- **Business Objective**: [What problem does this solve?]
- **Affected Services**: [Which microservices are impacted?]
- **Scope**: [New entity? New command? UI change?]

Step 1.2: Codebase Investigation

# Find related entities
grep -r "class.*{RelatedConcept}" --include="*.cs" src/

# Find existing patterns
grep -r "{SimilarFeature}Command" --include="*.cs"

# Check domain boundaries
grep -r "namespace.*{ServiceName}\.Domain" --include="*.cs"

Step 1.3: Pattern Recognition

• [ ] Find similar features in codebase
• [ ] Identify which patterns apply (CQRS, Event-driven, etc.)
• [ ] Check for reusable components
• [ ] Map dependencies

Phase 2: Impact Analysis

Backend Impact

### Domain Layer
- [ ] New Entity: `{EntityName}.cs`
- [ ] Entity Expressions: Static query expressions

### Application Layer
- [ ] Commands: `Save{Entity}Command.cs`
- [ ] Queries: `Get{Entity}ListQuery.cs`
- [ ] Event Handlers: `{Action}On{Event}EntityEventHandler.cs`
- [ ] DTOs: `{Entity}Dto.cs`

### Persistence Layer
- [ ] Entity Configuration: `{Entity}EntityConfiguration.cs`
- [ ] Migrations: Add/Update schema

### API Layer
- [ ] Controller: `{Entity}Controller.cs`

Frontend Impact

### Components
- [ ] List Component: `{entity}-list.component.ts`
- [ ] Form Component: `{entity}-form.component.ts`

### State Management
- [ ] Store: `{entity}.store.ts`

### Services
- [ ] API Service: `{entity}-api.service.ts`

Phase 3: Approval Gate

CHECKPOINT: Present plan to user before implementation.

Phase 4: Implementation

Backend Implementation Order

1. Domain Layer First — Entity, expressions, validation
2. Persistence Layer — Configuration, migration
3. Application Layer — Commands, queries, DTOs
4. API Layer — Controller, endpoints

Frontend Implementation Order

1. API Service — Extend PlatformApiService
2. Store — Extend PlatformVmStore
3. Components — Extend AppBaseComponent / AppBaseVmStoreComponent

Phase 5: Verification

• [ ] Entity compiles without errors
• [ ] Command handler saves entity correctly
• [ ] Query returns expected data
• [ ] API endpoint responds correctly
• [ ] Frontend loads data and renders
• [ ] Error handling works
• [ ] Authorization applied correctly

Anti-Patterns to AVOID

• Starting implementation without investigation
• Implementing multiple layers simultaneously
• Skipping the approval gate
• Not following existing patterns

Related

• feature
• tasks-code-review
• tasks-test-generation

IMPORTANT Task Planning Notes (MUST FOLLOW)

• Always plan and break work into many small todo tasks
• Always add a final review todo task to verify work quality and identify fixes/enhancements