Definition:
A concierge MVP is the best approach to get to know your customers and validate your business idea. In this you provide the service manually and analyze your audience, this type of MVP allows you to pivot easily if you find out that customers actually want a different product.
The point of the Concierge MVP is to simplify the product by replacing automated components with humans. Every customer receives the white-glove treatment, with humans front and center delivering the service.
Further Reading:
Book: The Lean Startup by Eric Ries