The AWS Well-Architected Tool lets you review a workload against the Well-Architected Framework and other lenses by answering questions in the AWS Management Console. It then gives you an improvement plan with a prioritized list of issues. AWS charges nothing extra for the tool itself.
What a review is
A workload is a collection of resources and code that delivers business value, such as a customer-facing application or a backend process.
AWS describes a Well-Architected review as a constructive conversation about architectural decisions, not an audit. It gives you a consistent way to measure an architecture against best practices and find areas to improve.
AWS recommends doing a review at major milestones in your development cycle.
What the tool shows you
You define a workload and answer questions for each pillar. The tool evaluates your answers and produces an improvement plan with a prioritized list of issues.
For each workload it shows the number of questions answered, the number of high risk issues (HRIs) and medium risk issues (MRIs), and an improvement status you set. HRIs are choices that AWS found might cause significant negative impact to a business. MRIs might also cause harm, but to a lesser extent.
Lenses and milestones
A lens is a set of questions, best practices and an improvement plan. The Well-Architected Framework Lens is applied automatically when you define a workload.
Lens Catalog lenses are official lenses created and maintained by AWS. Custom lenses are your own: you write the pillars, questions, best practices and improvement plans, and you can share them with other AWS accounts.
A milestone records the state of a workload at a point in time. Save one after you first answer all the questions, then save another each time you make improvements so you can measure progress.
Where the exam catches people
Believing a Well-Architected review is an audit: AWS says it is a constructive conversation about architectural decisions, not an audit mechanism.
Believing a custom lens comes from AWS: custom lenses are user-defined; AWS-maintained lenses are in the Lens Catalog.
Believing a milestone is a step in the improvement plan: a milestone is a saved snapshot of the workload's state at a point in time.
Believing the tool records API calls or compliance reports: it reports questions answered, high and medium risk issues, and improvement status.