Thank you, Mark and others for your work on this document to update the specification. My comments are mainly requests for clarity in the document and text suggestions are provided to hopefully make this as easy as possible. 1. Section 3: Nit: In my opinion, the flow would be improved if the third paragraph came before the current second paragraph. 2. Could you provide a transitional sentence between the current second paragraph and the instructions that follow since the current second paragraph points to following section 5.1 for instructions, but paragraph 4+ include instructions or guidance followed by additional helpful information. I think a slight adjustment as follows to accomplish this would be quite helpful to the reader: Applications that wish to mint new well-known URIs MUST register them, following the procedures in Section 5.1 and the following requirements. 3. Section 3.1 says: The "Well-Known URIs" registry is located at "https://www.iana.org/assignments/well-known-uris/". Registration requests can be made by following the instructions located there or by sending an email to the "wellknown-uri-review@ietf.org" mailing list. I'm not clear on the instructions as I follow the link to the registry and there's a pointer to the RFC that this document will obsolete. I'm assuming that the reference will be replaced with this document. Is that the case or are there additional instructions than what will be included directly in the registry? If they are repeated (I don't see an IANA request for that action), that is fine, but I think it's a little confusing to send someone to that link if they are already reading this document. This document is also going through a review process to update that registry, so if instructions were maintained at the registry URL, what would be the review process to alter the instructions? I'm assuming that this sentence just should be removed, but if not, I'd like to understand the update process for that registry (instructions for registering values not adding them). If the sentence should be changed, I suggest something like: The "Well-Known URIs" registry is located at "https://www.iana.org/assignments/well-known-uris/". Registration requests can be made by following the instructions in this document and sending the email to the "wellknown-uri-review@ietf.org" mailing list. 4. Question on Change controller: Is it possible to successfully make a request through an experimental track RFC or standards track only? If experimental is allowed, can it only be provisional? 5. Section 3 has the following sentence: General requirements for registered relation types are described in Section 3. Did the document in a previous revision contain something in section 3 about registered relation types or am I missing something when reading section 3 (which is entirely possible)? If it were there (or maybe was in a previous revision), I'd expect to see it in the following paragraph, but could see the above text being dropped as an answer to this question as well (unless I am missing something): It MAY also contain additional information, such as the syntax of additional path components, query strings and/or fragment identifiers to be appended to the well-known URI, or protocol-specific details (e.g., HTTP [RFC7231] method handling). 6. Section 3.1: Is the following referring to IETF standards-track documents or could other standards from other SDOs (or some other constraint) be included? Standards-defined values have a status of "permanent". Other values can also be registered as permanent, if the Experts find that they are in use, in consultation with the community. Other values should be registered as "provisional". I'm guessing a standards track RFC is not necessary for standards track because of the next paragraph in this section, but maybe some added text would help to clarify the above paragraph? Provisional entries can be removed by the Experts if - in consultation with the community - the Experts find that they are not in use. The Experts can change a provisional entry's status to permanent at any time. 7. Section 5.1 second paragraph has the following text: Well-known URIs are registered on the advice of one or more experts (appointed by the IESG or their delegate), with a Specification Required (using terminology from [RFC8126]). This should read as follows according to RFC8126 section 5.2.1: https://tools.ietf.org/html/rfc8126#section-5.2.1 Well-known URIs are registered on the advice of one or more experts (appointed by the IESG), with a Specification Required (using terminology from [RFC8126]). There's no provision for the IESG to delegate assignment of an expert. IESG member often consult working group chairs and experts, but the assignment is currently performed by the IESG unless RFC8126 gets updated. 8. Section 5.1: (additional context for #5) Text adjustments in section 3 similar to what was proposed above may help avoid confusion when someone reaches this text on requirements in section 3 so that they are grouped and called out specifically as requirements. (No change suggested here, but rather just expanding on the desire for clarification above). The Experts' primary considerations in evaluating registration requests are: o Conformance to the requirements in Section 3 o The availability and stability of the specifying document o The considerations outlined in Section 4 9. Section 5.1: There may be additional information I am not aware of, hence the following clarifying questions. Is there a hold on the registry from now until this document is published? Could an expert receive a request prior to publication where they feel the right status is "provisional" and is timely (cannot wait until after actions for this document are complete)? I'm asking because of the following text and the answer may be yes, there is a hold, but I am not seeing where one is listed. Since the expert can update the registry at any time, is the second bullet necessary (could it cause problems)? Upon publication, IANA should: o Replace all references to RFC 5988 in that registry have been replaced with references to this document. o Update the status of all existing registrations to "permanent". ------- 10. For the IESG: Are there plans to name a second expert in case Mark isn't available? ----- I hope you find these comments helpful to further clarify the text of this document. Thank you, Kathleen