Bhagavad Gita, Chapter 7, Verse 2

I shall tell you in full, of knowledge, speculative and practical, knowing which, nothing more here remains to be known.

This is being framed as the real, complete picture, not one more piece among many.

That's a genuinely bold claim, and Krishna makes it directly. What follows isn't presented as partial insight to be supplemented later, it's offered as the whole thing, nothing left over to discover beyond it.