Thomas Ptacek: Never use a word an LLM suggests

Thomas Ptacek's rule sits at the center of a broader piece about how to use LLMs in writing. The article positions LLMs as copyeditors rather than writing assistants, a distinction that runs through the examples. The rule to never use a turn of phrase suggested by an LLM is described as feeling good, and the text's "weird smell" is given as one reason. The article notes it is also a good principle to help stay disciplined.

Simon Willison, whose blog hosts the piece, echoes the sentiment. He writes that he won't let LLMs write content for his blog, but uses them for fact-checking, spelling and grammar, and as an occasional thesaurus. The article links to his proofreading prompt. The piece later shows Thomas's personal LLM copyediting tool and provides a prompt to help kickstart building your own.

The stakes appear to hinge on whether writers can hold a strict line against LLM-suggested wording while still using LLMs for the tasks the article permits. For blog authors and editors weighing how much of their prose to run through an LLM, the piece offers a concrete rule to test rather than a general argument about AI writing.