Run script automatically when file is in hotfolder

I will try to be more precise. 

The AI is installed on the server computer (MAC), the script I created automatically opens all the files from the input folder, converts them and saves them to a specific location, and that works perfectly when i access script manualy.  My problem is that I don't know how to trigger the script every time a file arrives in the input folder. An additional limitation is that due to the company's policy I cannot install  any additional software.

Thank you all for your dedication. 

I achieved something like this by using a custom Adobe Bridge script that listened for folder changes, if a file of a certain format was found it ran a script and then moved the file to a completed folder. Worked well for what i required.  If you're familiar with scripting, it maybe a good option.

Believe this maybe the post or similar that i  used to learn it

https://community.adobe.com/t5/photoshop/watch-folder/m-p/4574941

If you're on Mac "Keyboard Maestro" is another way to setup "Watched Folders" and much more.

you'll likely need to do some combination of automator and applescript (or the pc equivalent which i'm not familiar with).

I'm not entirely sure how you'd trigger the script. you could set up an action in illustrator that executes the script, and you could set a hotkey to that action, and you could use automator or applescript i believe to send some keystrokes to illustrator to trigger the action.

And as AndrewH said, you can attach "Folder Actions" to your hot folder so that when a new file is added, the folder action will execute and trigger your applescript which triggers your action which triggers your script.

If there's a less convoluted way to do this, i'd love to hear about it. Because honestly all of that is a bit ridiculous.

You can create watch folders in various ways on Mac and Windows. On Mac I think I used Automator. "Mac Automator watch folder" should bring up plenty of options/ideas. On Windows I think I did it via Powershell/the terminal.