Lol, "Marxist literature defines state capitalism as a social system combining capitalism with ownership or control by a state".
Excuse me, when I respectfully decline that definition. What makes or breaks capitalism is private property rights, including the means of production.
"Engels argued that the tools for ending capitalism are found in state capitalism", that's like saying that eating your steak well done gives you the tools for slaughtering the cow.
OTOH, "It is not commonly realized that State Capitalism covers nothing more than what used to be called Planned Economy and State Socialism, and that State Capitalism, Planned Economy, and State Socialism diverge only in non-essentials from the classic ideal of egalitarian Socialism". At least one can find some sensible definitions in the article.
> State capitalism is an economic system in which the state undertakes business and commercial (i.e. for-profit) economic activity and where the means of production are nationalized as state-owned enterprises (including the processes of capital accumulation, centralized management and wage labor). [...] Other examples include Singapore under Lee Kuan Yew and Turkey, as well as military dictatorships during the Cold War and fascist regimes such as Nazi Germany.