"we should clarify" is correct and usable in written English.
You can use it when you want to suggest that two people should discuss something in order to make the meaning or purpose of it more understood or precise. For example: "We should clarify our plans for the weekend before making any decisions."
We should clarify that the FAO bases its figures on annual landings of fish, not catches.
We should clarify that this was an incident where the military slew over 700 children, women, and men.
We should clarify that while airspace capacity was restricted after an air traffic control computer fault forced about 100 flights to be cancelled, it was never closed.
We should clarify that less than 1% of the £8.5m funding he has won since 1998 has come from the industry.
We should clarify that, while Hizb ut-Tahrir has lobbied for other nations to become caliphates, its UK wing does not campaign for Britain to become one.
We should clarify that because the Analysis by Ellingsen and co-authors is part of a special issue, we allowed it a special format.
He writes: Rather than get defensive at Diane's defeatism, we reformers should clarify the ends that education reform can achieve.
Further investigation of the phenotypes we observe should clarify which aspects of cellular metabolism require mitochondrial potential.
Update: I should clarify what we mean when we refer to 'unsigned apps'.
Osterloh sent us this additional comment after we published: "Regarding the future of Google-branded laptops (whether called Pixel or not), I should clarify that we don't have any plans to discuss at this time".
Well, first I should clarify that we are not arguing that racial status threats were the most compelling reason for someone to support the Tea Party.
