Detail is not really the issue. I can spend all day writing a big monster and describe it down to every last scale, tooth, and claw, but if the idea and narrative supporting the article are weak, then it'll be a weak article.
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SCP-2593 is to be kept in its cell, a dark, 5 m x 5 m x 5 m
airtight steel chamber, at all times
Are the exact dimensions of the cell crucial to containment? What about the material make-up? Why does the cell need to be airtight or dark? From your description light would make this creature easier to contain if anything.
Muscles do not really function like that. Organic propulsion operates considerably differently from a simple spring.
research suggests the creature can run up to increased speeds of about 50 mph and can jump upward 18 feet from a sitting position. It also can leap up to 40 feet horizontally. Arms are about 0.63 meters long each with hands ending in 3.5 inch retractiles.
We use metric here (kph, m, & cm rather than mph, ft, in)
SCP-2593 has no eyes and has a melon shaped bump on its head below the jaw believed to contain sensory organs which facilitates sonar that's around 40 to 150 kHz.
Neither "melon shaped" nor "around" are very clinical phrases.
It is believed that this sound is used to see
I understand the oversimplification here, but using echolocation/sonar to navigate isn't really seeing per se. I would suggest just using "navigate" or "perceive its environment".
SCP-2593 also has a unique cell system called chromatophores just below the surface of the skin which helps it camouflage itself.
I wouldn't say unique, really. Chromatophores can be found across the animal kingdom, from mollusks to amphibians to fish to crustaceans.
SCP-2593 will also try to alter its body shape by softening it's bone structure
Skeletons are, by design, relatively hard and inflexible. How exactly would something regulate its bones like this?
Despite being a hairless white creature, SCP-2593 has tiny hairs on its hands and feet which helps it climb.
Having hair means it is not hairless, by definition. Also I'm not sure you should assign it a color when the nature of chromatophores means its color is not static.
The big problem with this article is that it's pretty uninteresting. You threw a bunch of predator traits together to make a big scary monster, but you're not telling any sort of story and this article lacks any sort of compelling element to keep a reader engaged or entertainment. I would strongly suggest that on your next attempt you think about the question words (why is this creature here? Where did it come from? How did the foundation find it? What is it and what does it want? etc.)
It would also be a good idea to create a sandbox page so you can receive feedback on your next article before posting here to the mainsite.