AIP-158 INVALID_ARGUMENT?

[chrisjshull]

Hi,

https://google.aip.dev/158 states...

Request messages for collections should define a string page_token field, allowing users to advance to the next page in the collection.
...
The user is expected to keep all other arguments to the RPC the same; if any arguments are different, the API should send an INVALID_ARGUMENT error.

Why insist on the user sending the all other arguments again? Why not also allow the user to send just the page_token? Perhaps naively, that seems easier from a user perspective.