I have worked with on the s/38 since the 1980’s. Trying to write your own debugger is a major task. What do you hope to accomplish that the IBM debugger cannot provide? I don’t recall seeing the “Option” value of an object showing up where you would have access to it. There may be an API but I have not run across it. You may want to check out some of the IBM forums and see if they can point you in the right direction. Check out the link here.