The news is bad for a porter (6)
I believe the answer is:
report
'the news' is the definition.
(report is a kind of news)
'bad for a porter' is the wordplay.
'porter' anagrams to 'REPORT'.
But, I am not clear how the anagram is indicated.
'is' is the link.
Can you help me to learn more?
(Other definitions for report that I've seen before include "Announce; gunshot" , "Inform about the sound of thegun" , "Gunfire noise; rumour" , "Make a complaint about (someone)" , "A loud bang, or an account" .)