This is the 13199th most frequent Russian word.
минских
"Минских" means "of Minsk" or "Minsk's" (possessive form, relating to the city of Minsk, Belarus).
The word 'минских' is an adjective here, describing 'agreements' (соглашениях) originating from or pertaining to Minsk.
Я прочитал статью о минских соглашениях.
I read an article about the Minsk agreements.
In this sentence, 'минских' describes 'сights' (достопримечательностей), indicating that the sights are located in Minsk.
Туристы посетили несколько минских достопримечательностей.
Tourists visited several sights of Minsk.
Here, 'минских' modifies 'negotiations' (переговоров), indicating they took place in Minsk.