Document field name rules

Field names cannot start with $.

Field names cannot be exactly *.

If a field name includes & or ., you must escape those characters when you use the field in a filter, sort, projection, or update. For more information, see Work with . and & in field names.

_id: An optional unique identifier for the document. If _id is omitted, it is created automatically based on the collection’s ID type. For more information, see Document IDs.

$vector: An optional array of numbers representing a vector embedding for vector search. The $vector field is only supported for vector-enabled collections. A document cannot contain both a $vector and a $vectorize field. For more information, see $vector in collections.

$vectorize: An optional string from which to generate vector embeddings for vector search. The $vectorize field is only supported for collections that have an embedding provider integration. A document cannot contain both a $vector and a $vectorize field. For more information, see $vectorize in collections.

$lexical: An optional string to make the document searchable for lexicographical matching and the lexical search component of hybrid search. The $lexical field is only supported for collections that have lexical search enabled. For more information, see $lexical in collections.

$hybrid: An optional string that populates both $vectorize and $lexical. The $hybrid shorthand is only supported for collections that have vectorize and lexical search enabled. If a document uses $hybrid, it cannot contain a root-level $vectorize or $lexical field. For more information, see $hybrid in collections.