I have a friend coming from Brazil to stay with me in Paris for some weeks. Does he need an Attestation d'accueil even if his flight has a connection in another country in the Schengen Zone? (which means that he won't make the immigration process in France, so a simple letter should work, right?)
The definition of this document is:
An "Attestation d'Accueil" is a document required if you are going to France and planning to stay with friends or relatives for a period of less than 3 months.