app.didpic.write.createComment

Create an app.didpic.feed.comment record on the authenticated viewer's own PDS, mediated by the AppView using its server-held session (confidential OAuth client only). image, when present, must come from a prior app.didpic.write.uploadBlob call. Either text or image (or both) should be present — matching the underlying record lexicon, this isn't enforced here either.