Well written and easy to read; thanks. I only have some very minor editorial suggestions that I ask you to consider: — Section 1 — Many such capabilities are specific to either the complete system, individual YANG datastores [RFC8342], specific parts of the YANG schema, or even individual data nodes. Nit: “either” is correctly used for two items (“either A or B”). For the four items here, you might just eliminate the word “either”, as it’s not really needed. A NMS implementation that wants to support notifications, needs the information about a system's capability to send "on-change" notifications. I often find that I have to read this sort of thing (“A needs B to do C”) twice to determine whether you mean that A requires that B do C, or that A needs B so that A can do C — it’s ambiguous, so it requires extra analysis by the reader. I suggest the following (which also eliminates the personification of NMS): NEW An NMS implementation that supports notifications needs the information about a system's capability so it can send "on-change" notifications. END — Section 2 — This allows a user to discover capabilities both at implementation-time and run-time. Nit: The “at” is factored wrong with respect to “both”. Either “both at implementation time and at run time” or “at both implementation time and run time”. In either case, no hyphens here, as they’re not compound modifiers. The file MUST be available already at implementation-time retrievable in a way that does not depend on a live network node. Nit: No hyphen (again, not a modifier), and it needs a comma after it: “implementation time,” For the run-time use-case Nit: Here, “run-time” is a modifier and needs the hyphen, but “use case” is a noun and does not. (implementing the publisher) during run-time. Implementations that support changing these capabilities at run-time SHOULD Nit: No hyphens in “run time” for these two (nouns, not modifiers). — Section 3 — A specific case is the need to specify capabilities is the YANG-Push functionality. I’m not sure of the right fix for this, but the two instances of “is” can’t both be right. Maybe the first should be “of”? As defined in [RFC8641] a publisher may allow subscribers to subscribe to updates from a datastore and subsequently push such update notifications to the receiver. It’s unclear who is pushing: it looks like it could be the subscribers. Maybe clarify this way?: NEW As defined in [RFC8641] a publisher may allow subscribers to subscribe to updates from a datastore and will subsequently push such update notifications to the subscriber. END unless the subscriber has some means to identify which objects "on-change" notifications are supported. Missing word: “are supported for.” — Section 4 — It SHOULD be used by other modules to augment-in specific capability information. The term “augment-in” is not one I’m familiar with. If it’s common in YANG, that’s fine. If not, maybe rephrase? data is considered as if it was part of the running datastore. Ultra-nit: “as if it were part”: subjunctive mood is needed after “as if”.