The Phantom Method: When GPT Hallucinated Itself Into Recursion
A developer asked an LLM for help with a library API and was given a method name that didn't exist. Googling revealed only one other result—a GitHub issue where someone else had been told the same fictional method by another LLM.
A staff engineer reached for GPT to solve a coding problem in an unfamiliar library. The model confidently suggested calling a specific method. The developer had never heard of it—a red flag—so they Googled. One result. Just one.
That result was a GitHub issue. Someone else, somewhere, had also been steered toward the exact same nonexistent method. They'd also been confused. They'd also gone looking for answers. The probable culprit? Another LLM had hallucinated the same fake API call.
Two people, two separate LLM interactions, one shared phantom method, cascading down the internet like a ghost story propagating through séances. Neither developer's problem was solved. Both wasted time chasing a ghost.
Original post
gpt recommended I call a method I hadn't heard of in a library I'm using. so I googled it. 1 other result.
— Matt Popovich (@mpopv) December 3, 2023
turns out, it doesn't exist. gpt hallucinated it. but someone had asked about it on github... because an llm had hallucinated the same method name before.
it begins. https://t.co/QVohLcbx3t
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