Is there any API that I can use to retrieve information displayed in "Info" panel?

[RongZhang]

When I move the mouse or make a selection across a layer, the "Info" panel will update information like color (RGB & CMYK), mouse position and the width and height of current selection.

Any API to get the information?

[ilvar]

For the mouse position, the general answer is no. The API to get the mouse cursor position has been requested by third-party developers like ourselves for quite some time and you are welcome to add your voice to it, since it hasn't been implemented. As for the rest, you can register your automation plugin to receive notifications on various events and retreive the selection upon them. Note that there are a lot of different events that may affect your selection info, starting from switching to a different document, to actual selection change etc, and you'd have to perform the update on all of them to keep the displayed information current. Ditto for the color mode. But it IS certainly doable.