form-validation-design

What problem does it solve?

This Skill solves the risk of insecure or unreliable form validation by specifying a production-ready contract where the backend is the enforcement boundary while the frontend delivers fast, field-precise UX.

Core Features & Use Cases

• Backend-enforced validation boundary: Guarantees every rule (format, ranges, business constraints, authorization, uniqueness) is enforced on the server even if the client is bypassed.
• CSRF and duplicate-submit protection: Defines CSRF requirements for every state-mutating mutation and enforces idempotency via Idempotency-Key to prevent duplicate side effects.
• Race-condition-free async checks: Uses debounce, AbortController cancellation, and stale-result invalidation so async validation never marks the wrong value as valid.
• Field-precise error mapping and recovery: Maps RFC 7807-style violations to specific fields with actionable messages, preserves user input, and supports partial-failure recovery for bulk/multi-step flows.

Quick Start

Tell the AI to design your form validation and submission lifecycle so backend enforcement, CSRF safety, idempotent retries, and field-level recoverable errors work correctly.