Inconsistent use of plural in the description of headers

[Maxime-Daniel]

https://cloud.ibm.com/docs/api-handbook?topic=api-handbook-headers
'For requests including this header, the server SHOULD attempt to return resources encoded in an acceptable way.'
('resources')
versus
'For requests including this header, the server MAY attempt to return resource in an acceptable language.'
('resource')

IMO the former is better from an English perspective... but I am French...
In any case there is no reason for not using either a plural or a singular in both places.