A bot that integrates with Slack to search for gifs for you.
In the top left corner of the Slack UI, click the down arrow and select Configure Integrations.
Scroll down the list of integrations, and click on Outgoing WebHooks.
On the next page, click Add Outgoing Webhook and scroll down to the Integration Settings section.
Choose a trigger word (or words) and enter the URL to your gif bot instance. Optionally, customise the name and icon of your bot before clicking Save Integration.
If all has gone well, you'll now be able to use it in your Slack channels.