The origin (0, 0) is at the top left corner of the canvas. All positions are relative to the origin.
Command  Arguments  Description  Defaults 

canvas 
width: number ,height : number

sets the artboard dimensions  400x400 
size 
strokewidth: number

sets the stroke size  1 
stroke 
strokecolor: color

sets the stroke colour  #333 
fill 
fillcolor: color

sets the fill colour  none 
move 
strokewidth: number

moves the pen to a new position  
line 
x: number ,
y: number

draws a line from the current position of the pen to the specified position  
horizontal 
x: number

draws a horizontal line from the current position of the pen to the specified x position  
vertical 
y: number

draws a vertical line from the current position of the pen to the specified x position  
cubic 
x1: number ,
y1: number ,x2 : number ,
y2: number ,x : number ,
y: number

draws a cubic bezier curve with two control points  
reflect 
x2: number ,
y2: number ,x : number ,
y: number

draws a cubic curve where first control point is a reflection of the previous curve's second control point – must follow a cubic or reflect command  
quad 
x1: number ,
y1: number ,x : number ,
y: number

draws a quadratic bezier curve with one control point  
chain 
x: number ,
y: number

draws a quadratic bezier curve where the control point is inferred from control point of the previous curve – must follow a quad or chain command  
close  draws a line from the current position back to the starting position of the path 