Suppose I have a string, "my first task", that I know is tagged with "laptop".

I want to search through the agenda files for a headline that matches this string, to be able to mark it as DONE (in an automated fashion).

I can't find a function to search through for the headline --- is there one?

Else, is it best to concat all the agenda files into a larger buffer, then parse the buffer and iterate through the headlines with org-element-map?

Cheers,

Chris