run-llama/crossposter ? reverse-engineered prompt

Build me a web app that lets me write one social post and then publish it to multiple platforms at once.

I want the app to help adapt the same message for each network, so it can shorten the text when needed and turn names into the right @ mentions automatically. It should support signing in with Google, connecting social accounts, and storing user access tokens securely. I also want it to be able to search the web when needed to help with the content. Make the interface simple enough that I can paste in a post, pick the places I want to send it, preview the version for each platform, and then post it.

If you need to look up current docs online for any of the APIs or auth setup, go ahead. Please keep it working locally with a normal dev setup and make it feel like a real internal tool that is useful right away.