Macros of the documentation library, specifically docKey, can contain numerous ⟨parameters⟩. In this a case, these ⟨parameters⟩ may overlap the ⟨description⟩ and even extend into the margin:
\documentclass{article}
\usepackage{tcolorbox}
\tcbuselibrary{documentation}
\begin{document}
\begin{docKey}{foo}{%
\colOpt{=%
foobarbaz1\textbar foobarbaz2\textbar foobarbaz3\textbar foobarbaz4\textbar
foobarbaz5\textbar foobarbaz6\textbar foobarbaz7\textbar foobarbaz8\textbar
foobarbaz9\textbar foobarbaz10%
}%
}{initially \texttt{foobarbaz1}}
\end{docKey}
\end{document}
It would be nice if the tcolorbox documentation library could automatically handle such long ⟨parameters⟩.