Validate List Item Length

I have a dynamic list that occasionally comes through empty, and I want to be sure that, as items get added, every single entry respects one rule only: Specific length — each item must be less than 10 characters long... (Budget: ₹750 - ₹1250 INR, Jobs: Copy Typing, Debugging, JavaScript, PHP, Programming, Python, Software Architecture, Software Development, Software Engineering)