The diagram
Every HTTP response is a decision.
Send a request from the rail, or call this page's live URL with curl, and watch the flowchart decide the status one question at a time.
WebMacha sandbox
The PUT targets /widgets/9, which does not exist yet, so I7 sends it down the PUT branch and P3 finds no conflict before the body is accepted. P11 asks whether a new resource was made; it was, and RFC 9110 §9.3.4 says a PUT that makes one must answer 201 Created. No Location was set, so Location is the request's own URI.
Decision flow
Decision path
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Request log
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