Jq
jq is a command line JSON processor, this works really well in tandem with HTTPie.
Usage
Get all elements from array response
jq '.[]'
Filter those elements on a key
# truthy test
jq '.[] | select(.mykey)'
# specific values
jq '.[] | select(.mykey === 'some value')'
Return only a specfic key from an array result
jq '.[].mykey'
Return a specific element's value based on a filter on a key in an array response
jq '.[] | select(.id == 123).mykey'