And the other approach says that the text is a series of “tokens,” using e.g. the definitions you give here.   That is the first stage of a good parser ... the so-called “lexer.”   The fun begins when you have to deal with the structures that this stream-of-tokens can take.   That is the upper-half of a parser ... and the point where its real power comes to play.

I say this, merely to describe situations where a full-blown Parser is extremely useful.   If “all that you really need is a lexer,” and the structure of the “language” is so straightforward that you really are not in need of decision-making to decide what you have and/or what to do, then a Parser might (or, might not ...) be overkill.   The time to make these decisions is early.