We’ve been busy working on technical documentation to share with you on best practices for Custom Content and Mods and details about how the game works. We’re happy to announce that this can now be found here: TS4_Custom_Content_Guide.zip
The Sims 4 is a large game, so we can’t document everything about it, but we’ve included information about a few key things we thought you’d appreciate.
We hope this accelerates your progress. Please continue to ask questions in the forums, and we will do our best to answer them.
Thanks again for all your hard work and awesome creations.
UPDATE: Please see this thread for the most up to date information from Maxis.
Please note that we do not pre-screen Custom Content and that players should always exercise caution when adding Custom Content to their game files.
The terms and conditions set out in The Sims 4 End User License Agreement (ea.com/1/product-eulas) and EA's Terms of Service (ea.com/terms-of-service) are applicable to the use of The Sims 4 product and services and all materials distributed by Maxis that relate to creating Custom Content and Mods for The Sims 4.