Most of the software developers hates meetings. Especially if they have no additional value for the development.
Ok it is clear, some of them are boring, but still needed. On the other hand some of them makes totally no sense for the whole development team. Of course just to decline a meeting is really not nice. What else can you do?
First of all never attend any meeting which has no agenda in the invitation. If so, then send an answer and ask for the agenda. Once you have an agenda go through and check which points can be relevant for you. If there are no relevant points ask the organiser why he/she invited you and what he/she would like to discuss with you. If there’s no “good” answer, you can simple tell that you feel it unnecessary to attend the meeting and if it’s ok you won’t join.
If only a part of the points are relevant for you, then you can suggest to the organiser to organise the agenda in a way that all relevant points are after each other and you are only attending to that part and not to the other ones.
If most of the points are relevant, but you still don’t wanna attend then check who are the other invited ones. If there’s someone else who has more or less the same knowledge in the relevant topics as you (like a teammate) then tell it to the organizer that you think it would be more effective (effectivity, it is an important keyword if you wanna ensure a manager!) if only one of you would attend. Once the organizer said yes to that ask the colleague if he/she plans to attend the meeting. If the answer is yes you don't need to attend.
All things summarized never tell "no" directly. Try to show that it is not really necessary for you to join the meeting and try to show that participation on the meeting would decrease your effectivity.
That’s the way what is working for me, but if you have any better idea feel free to share with us!