Codex with GPT 5.5 is instructed not to reference goblins, ogres, or pigeons. Donald Iain Smith/Getty Images

OpenAI included a line in Codex's instructions restricting references to goblins, gremlins, trolls, and ogres.

The line appears four times in the code, and has spawned scores of memes about "goblin mode."

Sam Altman wrote on X that Codex was having a "goblin moment."

What do gremlins, raccoons, and pigeons have in common? They're all explicitly referenced in the instructions for Codex.

OpenAI's instructions for its coding agent have a personality guide.…