I would call him a compiler and editor. I have rummaged through some of his surviving papers at the British Library, and from them it is clear that people sent him a wide variety of accounts and stories that he then edited and put together to create his book(s). He did completely rewrite some of those submissions, but others he seems to have repeated verbatim. Certainly the accounts of various theological debates were repeated verbatim, for example. And he no doubt also wrote some himself.
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