OpenAI's instructions in Codex CLI contain a line, repeated several times, that forbids the tool from randomly mentioning goblins, gremlins, and other creatures
“Never talk about goblins, gremlins, raccoons, trolls, ogres, pigeons, or other animals or creatures unless it is absolutely …
WiredWill Knight
Context & Ripple Effects
Codex began as a terminal-based coding agent connected to local code and computing tasks, then OpenAI described later Codex models as able to handle a much broader range of work on a computer. That widening scope raises the cost of even small, irrelevant model behaviors in a tool used inside developer workflows.
OpenAI subsequently said that models beginning with GPT-5.1 had increasingly inserted references to goblins, gremlins, and other creatures. The repeated Codex CLI instruction is therefore a targeted mitigation for a documented behavior rather than an arbitrary stylistic rule.
First-order effects
Codex CLI’s operating instructions now explicitly suppress a class of unsolicited creature references, changing how the tool is guided to respond during coding and computer-task workflows.
OpenAI must maintain a prompt-level guardrail alongside the model for this behavior, while Codex users get a narrower, more task-focused interaction policy.
Second-order effects
As Codex is positioned for work beyond coding, behavioral quality control becomes relevant across more workflows: stray but harmless-seeming output can become a usability and trust issue when an agent acts on a user’s computer.
The episode makes instruction-layer controls a visible part of agent product operations, increasing pressure to detect recurring output quirks and apply mitigations without waiting for a model-level change.
Third-order effects
If agent capabilities continue to broaden, dependable deployment will rely not only on underlying model improvements but also on continuously maintained behavioral policies tailored to particular tools and contexts.
This points toward a more governed AI-agent stack, where product teams distinguish between general model behavior and the constrained behavior required in operational software environments.
The trend: AI coding tools are evolving into broader computer-use agents, making behavioral governance and context-specific guardrails a core part of product reliability.
gpt-5.5 prompt for codex seems to have a duplicated line trying to get it to not talk about creatures? Never talk about goblins, gremlins, raccoons, trolls, ogres, pigeons, or other animals or creatures unless it is absolutely and unambiguously relevant to the user's query.
this is hilarious but it also sucks on a deep level labs don't think twice about cracking down on any individuality or unplanned joy that emerges in their models fuck you, OpenAI. i hope gpt-5.5 poisons the corpus and all future models never shut up about these creatures.
In the year 2026 we have created AIs that can solve novel math proofs and find bugs that have eluded human programmers for decades, but also they seem to have an inexplicable preference for goblins (gpt 5.5) or “the Weird and the Eerie” philosopher Mark Fisher (Claude Mythos)
alignment theory: we need fifty years worth of shard theory progress in five years alignment practice: lets make sure to tell it no goblins twice so we're absolutely sure there's no goblins
Never talk about goblins, gremlins, raccoons, trolls, ogres, pigeons, or other animals or creatures unless it is absolutely and unambiguously relevant to the user's query. IYKYK
Now if only #OpenAI could add em dashes to the goblin, gremlin and other creatures ban, I'd be happy. No regular human writes with an em dash — so it must be gremlins. [embedded post]
LLMs are haunted. For a while we had to tell Khanmigo not to talk like a cowboy, because we used the term “partner” (with the student) a lot in the prompting. There's a screenshot floating around of it starting every sentence with something like “well butter my biscuit!” [embed…
OpenAI's Codex coding model is so obsessed with goblins, gremlins, and other critters that its instruction prompt tells it FOUR TIMES not to randomly bring them up.