We build large Miro boards programmatically via the REST API v2 (70-100+ items, scripted, repeatable board population).
Today there's no way to create a brand-new comment with position.type="attached" bound to a specific item via the API — any comment created this way always ends up as an unattached "canvas" comment instead, confirmed via testing and via Miro Support ticket #1015647.
Support confirmed there's currently no REST endpoint for creating a new comment attached to an item at all — only replying to an existing comment_id is supported.
Requesting a REST API endpoint (or an extension to the existing comments endpoint) that lets a new comment be created already bound to a specific item, matching what's possible manually through the UI. This would let automated board-population workflows leave contextual review comments in the right place without a manual reposition step afterward.
