I have observed the different profile result with regard to $comment query operator in association with find and update operation respectively as follows; - find operation shows a comment on the command.filter.$comment and the command.comment field in the system.profile collection. op: 'query', ns: 'db101.Bets', command: { find: 'Bets', filter: { _id: ObjectId("61a9db4b3bd34e4f68fb9abc"), '$comment': 'test-dba' }, comment: 'test-dba', lsid: { id: UUID("43ebee67-3184-4ede-9cee-ecca7457861a") }, '$db': 'db101' }, - update operation shows a comment only on the command.q.$comment field in the system.profile collection. op: 'update', ns: 'db101.Bets', command: { q: { _id: ObjectId("61a9db4b3bd34e4f68fb9abc"), '$comment': 'test-dba' }, u: { '$set': { odds: 0.5 } }, multi: false, upsert: false },