What problem does it solve? Adding a new service or MCP tool to AiRaccoon touches many moving parts—ports, adapters, DI registration, schema DDL, tool inventory tests—and doing it wrong ripples into dozens of existing fakes and test files. This Skill encodes the established patterns so new services integrate without breaking existing interfaces or the schema version ladder. ## Core Features & Use Cases - Port + Adapter Pattern: Guides creation of separate service interfaces (e.g., ISearchQualityService) instead of growing IMemoryStore, avoiding ripple into 15+ fake stores. - MCP Tool Class Pattern: Provides the full template for new tool classes with TN_* constants, ToolExecutionActivity wrappers, AccessRequirement tiers, and dual registration in CreateAppHost and CreateWebHost. - Additive DDL & Testing: Covers CREATE TABLE IF NOT EXISTS schema additions without version bumps, SQLite gotchas (nullable UNIQUE, redundant indexes), and the xunit v3 integration test pattern. - Use Case: When adding a search-quality tracking feature, follow the Skill to create the Core interface, Sqlite implementation, QualityTools class, DI registration, and integration tests without touching IMemoryStore. ## Quick Start Add a new injectable service and MCP tool to AiRaccoon following the port-adapter, DI registration, and integration test patterns in this skill.
