What problem does it solve? CloudFormation templates fail for many reasons—schema errors, security misconfigurations, name conflicts, and runtime IAM or quota issues—and diagnosing them requires knowing which tools and APIs to use at each stage. This Skill provides structured procedures for authoring templates with secure defaults, validating them before deployment, and diagnosing failed stacks without guesswork. ## Core Features & Use Cases - Template Authoring: Apply best-practice checklists covering secure S3 defaults, DeletionPolicy on stateful resources, parameter constraints, and avoidance of hardcoded resource names. - Three-Layer Validation: Run cfn-lint for syntax and schema, cfn-guard for security compliance, and change set pre-deployment validation via the describe-events API. - Failure Diagnosis: Retrieve failed events with the FailedEvents filter, correlate with CloudTrail in a ±60 second window, and classify fixes as template-level or environment-level. - Use Case: A stack is stuck in UPDATE_ROLLBACK_FAILED. The Skill pulls only the failed events, identifies the first real failure (e.g., an IAM permission gap), distinguishes it from cascade cancellations, and provides the exact IAM statement or template fix. ## Quick Start Ask the assistant to validate my CloudFormation template and troubleshoot why my stack deployment failed.
