What is the most easiest way to get the record schema for suiteqL queries in scripts ? (I want to get the schema in programmatic way)

Tim released a beta version of suiteql 2026.1 which has the ability to dump the tables into a usable format. I'd look at his script to see how he is doing it.

Is it open source?

It's released under MIT https://timdietrich.me/suiteql-query-tool/