> Can I just feed it a JSON object that represents a query and it will "work"?

You can use a query builder [1][2], although it's not exactly create a JSON object for a query but still better than directly writing SQLs and IMHO it's more clean than JSON object queries.

[1] - https://github.com/tgriesser/knex

[2] - https://github.com/hiddentao/squel