$vectorSearch filtering by ObjectId

MongoDB Atlas Vector Search
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What I had originally posted is what we use in production with the $search keyword for vector search aggregation queries:

$search: {
    index: 'vector-search',
    knnBeta: {
      vector: queryEmbeddings,
      path: 'embedding',
      filter: {
        equals: {
          value: new ObjectId(userId),
          path: 'userId',
    },
      k: 200,
    },
  },

The main drawbacks that I noticed while using this vs $vectorSearch keyword is that:

  1. Results are not ordered by score so we had to add extra aggregation stages to get the score { $meta: 'searchScore' } and then sort ascending by the score before we could limit to whatever number of documents we needed to return
  2. Because they’re not ordered, in some cases, the k field value had to be bigger than recommended so we would get all the relevant documents back
    From the tests we’ve done using $vectorSearch keyword, results seemed to be ordered by score { $meta: 'vectorSearchScore' } so that removes the need for some aggregation stages