There is only one baroness that Sparhawk knows that might be considered to be stroppy, which begs the question, what on earth was Melidere doing here, but Sparhawk has other things to think about. He can find out more about her later.

"And should I trust you to not simply show me a portal to the spaces between worlds, claiming that it will lead me home? You've made it clear that I offend you by being here, and my death would solve that, with no chance of a return. Unless I stumble upon your own secret."

Yep, Sparhawk still doesn't trust you Martel, and isn't shy about letting you know it. But he's still polite about it, until Martel brings up the barrenness. To play ignorant, or to acknowledge it?

"You know as well as I that Lady Sephrenia has many talents, which is why it remains an 'ought'," Sparhawk shades the truth. He doesn't dare to outright lie, as Martel knows him far too well, but the shading is near enough. It all depends on what Martel actually knows, or is just guessing at.