What does the cryptic crossword clue "Note message to go that's composed to irk another? (3,8,4)" mean?

The wordplay uses an anagram. anagram of NOTE + MESSAGE + TO + GO = GETSOMEONESGOAT The answer is GETSOMEONESGOAT.

Note message to go that's composed to irk another? (3,8,4)

Daily Mail Cryptic #16971 | 7 Down | 2022-11-18 flower