For developers doing the commercial work too.
Connect the code
Connect a GitHub repository so questions about the product are answered from what it does, not what the README claims.
Useful requests
Things that build
Prototypes and websites come back runnable rather than as descriptions. A prototype is a working, sandboxed build with network access blocked; a website is real pages.
See Prototypes and Websites.
Driving it programmatically
Everything you do in the app can be done over the API. Create a key with custom permissions rather than full access.