Giphy Messages does not work on OS X El Capitan! Send the author a message if you think you have a fix.
Make sure you drag and drop Giphy Messages into your Applications folder.
After you run the app, open Messages > Preferences and select Giphy.applescript as the AppleScript handler. Don't worry, we'll walk you through this in the app.Download Giphy Messages
The part of Giphy Messages that detects when you send a message (Giphy.applescript) needs to live in a special folder. That script needs to be able to find the rest of the app that searches for and sends gifs. We look for it in your Applications folder.
You can probably tell the second catveat is related. Messages needs to know the script that's handling message events.
Nope, sorry. It's only for Messages on your Mac.
It's probably there. You might need to quit and relaunch Messages for the app to see it.
That happens. It's a bug in the AppleScript. I'm sorry.
Let us know! Reach out to @DanaRSilver on Twitter. You can also open an issue on GitHub, if that's your kind of thing.
Yup! The project is open sourced on GitHub. There's more information about hacking and the project structure there. If you make a change you think other users would like, send us a pull request!