One text says the Lord incited David to count the warriors of Israel and Judah. The other text says that Satan incited David to count the warriors of Israel. (The Lord had forbidden this, as it displayed a confidence in military strength rather than in Yahweh’s power).
Compatibilists frequently cite this as an example of how Satan always carries out God’s plan. God’s plan, they insist, is always good, though Satan is evil in carrying it out. The “paradox”—or (I believe) contradiction—that this viewpoint creates is unnecessary. These texts do not imply that Satan always carries out God’s plan, only that he sometimes does so. In this case, God planned on judging Israel and so he allowed Satan to bring it about. For editorial reasons, the author of 1 Chronicles attributes the act to Satan while the author of 1 Samuel attributes it to God who allowed Satan to do what he wanted to do.
As a parallel example, we should consider the way God sometimes uses the sinful, violent tendencies of one nation to punish another nation. As punishment on Israel, for example, the Lord allowed a wicked Assyrian nation to have its way with Israel (Isa. 10). Yet, God then punished Assyria for being the kind of nation that could be used by God in this way. Sometimes–but not always–the wicked intentions of an evil nation (or an evil being) convene with God’s purposes.