HTTP Client Hints
RFC 8942, “HTTP Client Hints”, is an Experimental document published in February 2021 by I. Grigorik, Y. Weiss. The canonical text is published by the RFC Editor.
Abstract
HTTP defines proactive content negotiation to allow servers to select the appropriate response for a given request, based upon the user agent's characteristics, as expressed in request headers. In practice, user agents are often unwilling to send those request headers, because it is not clear whether they will be used, and sending them impacts both performance and privacy.
This document defines an Accept-CH response header that servers can use to advertise their use of request headers for proactive content negotiation, along with a set of guidelines for the creation of such headers, colloquially known as "Client Hints."
What “Experimental” means
Describes a specification that is part of a research or development effort, published so the community can gain experience with it.
The canonical text of RFC 8942 is hosted at rfc-editor.org. Available in HTML,TXT,PDF,XML.
- RFC 8941 Structured Field Values for HTTP
- RFC 8946 Personal Assertion Token Extension for Diverted Calls
- RFC 8957 Synonymous Flow Label Framework
- RFC 8959 The "secret-token" URI Scheme
- RFC 8962 Establishing the Protocol Police
- RFC 8963 Evaluation of a Sample of RFCs Produced in 2018
- RFC 8964 Deterministic Networking Data Plane: MPLS
- RFC 8965 Applicability of the Babel Routing Protocol