very well vs all right

very well is not an adjective while all right is an adjective.

Word	Noun	Adjective	Verb	Adverb
very well	No	No	No	Yes
all right	No	Yes	No	Yes

As adverbs, very well and all right are synonyms defined as:

very well and all right: an expression of agreement normally occurring at the beginning of a sentence

Other synonyms of very well include alright, fine, OK.

very well (adjective)	all right (adjective)
	being satisfactory or in satisfactory condition

very well (adverb)	all right (adverb)
quite well	an expression of agreement normally occurring at the beginning of a sentence
an expression of agreement normally occurring at the beginning of a sentence	without doubt (used to reinforce an assertion)
	in a satisfactory or adequate manner