Egg has been the gold standard of protein for decades. It's one of the most digestible, bio-available proteins around, with a perfect score on the 'Protein digestibility-corrected amino acid score' used to measure protein quality. This means that after digestion, it provides 100% or more of the indispensable amino acids required per gram.
Egg is what nature relies on to nurture a single cell into a fully formed chick. It has everything you need for growth. We've been eating eggs for millennia, it's the most digestible complete protein source found in nature. Your body doesn't need any special instructions, it knows what to do with it.