Who are the characters in the frame story the notorious jumping frog?

The most important characters in the frame story are Jim Smiley and the Stranger.

A frame story is a story within a story. So this story written by Mark Twain is allegedly about the writer coming to a village to speak to Simon Wheeler about Leonidas Smiley. However, then we see the beginning of the frame story, which is about how Jim Smiley and his frog were tricked by the Stranger.