pgfplots: How to get coordinates, draws as a style

I draw these two points

fill[cyan] (yticklabel cs:0.5) coordinate[](X2) circle(2pt); 
fill[red] (yticklabel* cs:0.5) coordinate[](X1) circle(2pt); 

So my question is: How could I have that as a style, so that I can say e.g.
begin{axis}[drawpoints, ....]
There must be something with path picture or insert path or…

It may be a curious question, but I need that for some measurement methods, and I want to be flexible where I use that method.

documentclass[a4paper]{article}
usepackage{pgfplots}

begin{document}
begin{tikzpicture}[]

begin{axis}[
clip=false, 
ylabel=yLabel,
every y tick label/.append style={draw}, 
every axis y label/.append style={draw}, 
]
addplot coordinates {(0,-500) (1,1) (2,2)};

fill[cyan] (yticklabel cs:0.5) coordinate[](X2) circle(2pt); 
fill[red] (yticklabel* cs:0.5) coordinate[](X1) circle(2pt); 
end{axis}
end{tikzpicture}
end{document}

documentclass[a4paper]{article}
usepackage{pgfplots}
pgfplotsset{
  drawpoints/.style={
    before end axis/.code={
      fill[cyan] (yticklabel cs:0.5) coordinate (X2) circle(2pt); 
      fill[red] (yticklabel* cs:0.5) coordinate (X1) circle(2pt); 
    }
  }
}
begin{document}
begin{tikzpicture}
begin{axis}[
drawpoints,
clip=false, 
ylabel=yLabel,
every y tick label/.append style={draw}, 
every axis y label/.append style={draw}, 
]
addplot coordinates {(0,-500) (1,1) (2,2)};


end{axis}
end{tikzpicture}
end{document}