Aws cloudformation validate-template

aws cloudformation validate-template --template-body file://template.yml
{
    "Parameters": [],
    "Description": "AWS CloudFormation Sample Template RDS_Snapshot_On_Delete: Sample template showing how to create an RDS DBInstance that is snapshotted on stack deletion. **WARNING** 
This template creates an Amazon RDS database instance. When the stack is deleted a database snpshot will be left in your account. You will be billed for the AWS resources used if you 
create a stack from this template."
}

AWS CloudFormation: [aws cloudformation | create-stack | list-stacks | delete-stack | update-stack | list-types | estimate-template-cost | validate-template | describe-stacks | deploy | drift detection], aws cloudformation get-template-summary, aws cloudformation describe-stack-events