Relevancy

• Scoring basics: clauses are added in conjunction with the score parameter
• Boost by field value or function thereof
• TF/IDF, BM25
• compound: additive clause scoring
• scoreDetails w/ demonstrative lab
• The key to solid relevancy - match lots of ways, let the best and most matched docs bubble to the top
• https://foojay.io/today/mongodb-search-score-breakdown/

Returning the score

The computed search score is available automatically through the $meta context. It can be added to documents using either $addFields or $project using {"$meta": "searchScore"}

Requesting score details

The complete formula used to compute the score can be enabled and returned. Generating the score details comes at a slight performance hit, so only do so for diagnostic purposes.

Like the score, once it has been enabled the score details can be returned using $addFields or $project.

• Enable the score details by setting "scoreDetails": true within $search
• The score details are then available using {"$meta": "searchScoreDetails"}