Clause acting as an object complement

If I take the sentences "The sky grew dark" and "They made him captain", the last word of each of these sentences is an object complement (adjective and noun, respectively).

If a similar sentence is made but with a clause attached at the end instead of one word, how could one tell how that clause functions?

Take for instance this sentence:

Books and words have made me what I am.

Here again the part "what I am" is an object complement that describes the object "me".

Is the clause an adjective clause or a noun clause?

Both an adjective as well as a noun would fit well at the end of this sentence (Books and words have made me smarter/a poet), so how can one tell in case of a clause appearing in such sentences?

Regards,