Error Taxonomy - Structured Error Classification

Unified error classification system ensuring every error in the stack has a code, category, severity, and user-facing message. Bridges the FastAPI ErrorResponse model with the Next.js ApiClientError class.

Description

Provides a structured error code taxonomy following the DOMAIN_CATEGORY_SPECIFIC format. Maps every runtime error to an HTTP status code, severity level, and user-facing message, ensuring consistent error handling between the FastAPI backend and Next.js frontend.

When to Apply

Positive Triggers

• Creating or modifying API error responses
• Adding new HTTPException raises in FastAPI routes
• Implementing frontend error handling or display
• Designing error boundaries for React components
• Reviewing error consistency across backend and frontend
• User mentions: "error handling", "error codes", "error messages", "error response"