503-frameworks-micronaut-validation

# Micronaut Validation Guidelines Apply Micronaut validation best practices at HTTP API boundaries. **What is covered in this Skill?** - Bean Validation annotations on DTOs and command models - @Valid / @Validated usage in Micronaut controllers - Validation groups and custom validators - Consistent mapping of validation failures to 400 responses - Safe and predictable validation error payloads **Scope:** Apply recommendations based on the reference rules and good/bad examples. ## Constraints Before applying validation changes, ensure the project compiles. After improvements, run full verification. - **MANDATORY**: Run `./mvnw compile` or `mvn compile` before applying any change - **SAFETY**: If compilation fails, stop immediately - **VERIFY**: Run `./mvnw clean verify` or `mvn clean verify` after applying improvements - **BEFORE APPLYING**: Read the reference for detailed rules and examples ## When to use this skill - Add validation support in Micronaut - Review Micronaut validation rules - Improve request validation in Micronaut REST APIs - Add custom validation constraints in Micronaut - Validate Micronaut configuration properties - Improve constraint violation handling in Micronaut ## Workflow 1. **Read reference and assess project context** Read `references/503-frameworks-micronaut-validation.md` and inspect the current project setup before proposing changes. 2. **Gather scope and decide target improvements** Identify requested outcomes, constraints, and the minimum safe set of changes to apply. 3. **Apply framework-aligned changes** Implement or refactor validation-related configuration/code following the reference patterns and project conventions. 4. **Run verification and report results** Execute appropriate build/tests and summarize what changed, what was verified, and any follow-up actions. ## Reference For detailed guidance, examples, and constraints, see [references/503-frameworks-micronaut-validation.md](references/503-frameworks-micronaut-validation.md).