While we can't fix the model, we should improve our prompting to improve the changes of the model using $date instead of ordinary ISO strings for querying MongoDB, as it won't work when the queried field is a date and not a string.

Example:

Prompt: "can you find me all movies updated in the last 20 years?"
Query:

{ "lastupdated": { "$gte": "2005-09-15T00:00:00Z" } }

Expected:

Query:

{ "lastupdated": { "$gte": { "$date": "2005-09-15T00:00:00Z" } } }

As in: https://www.mongodb.com/docs/manual/reference/mongodb-extended-json/#mongodb-bsontype-Date