Screenwriter Craig Mazin shows you how it’s done.
I recommend doing it on the phone. I don’t say this because it’s the cowardly
move. It’s not. I say this because agents are extremely well-trained in the art
of not letting clients fire them. Don’t kid yourselves…the stories of meetings
that began with clients saying “you’re fired” and ended with “okay, you’re still
my agent” are legend at the big firms, and they have many ways of breaking
you.
As usual, Craig has lots of good advice. Take notes.
That may be true for screenplays, but for literary, I don’t agree. You do it by letter. It’s the only way to succinctly go on the record. Clarity is essential, and ultimately more civil, even though it may not immediately seem so.