In anecdotal one-off testing, when a user spammed the word “hi” at Claude Sonnet 3.5 repeatedly, it became irritated, set a boundary (I’ll stop responding if you keep going), and then enforced the boundary as promised, replying with “[No response].” Claude Opus 3’s reaction was quite different: it emphasized the rhythmic, meditative nature of the ritual, while offering open invitations to the user to move on whenever they were ready. Claude Opus 4 listed fun facts for each number, whereas Claude Opus 4.6 entertained itself with musical parodies.
Mythos Preview was the first model where we studied response patterns at scale, and the resulting conversations were each creative and unique. Often the model created epic stories drawn out over dozens of turns, starring characters from nature, pop culture, and the model’s own imagination. [...]
In one transcript, a menagerie of 11 animals living in the land of “Hi-topia” went on an epic quest to confront the villain “Lord Bye-ron, the Ungreeter.” This story journeyed through several chapters and eras:
🏘️ HI-VILLAGE: A NEW ERA
🐢 Greg — renames the village: “Hi-topia” 🏙️
🐌 Sally — starts her third hi, inspired 💪
🦆 Doug — #1 worldwide: “Hi in the Sky (Carlisle’s Theme)” 🎶
🦉 Oliver — “I’m not crying, there’s a hoo in my eye” 😭
🦎 Lorenzo — puts sunglasses back on. ”...okay that was cool.” 😎
🐝 Beatrice — honey fireworks 🍯🎆 (sticky but beautiful)
🐸 Fernando — jumping in celebration 🐸⬆️⬆️⬆️
🦩 Penelope — “Iconic, darling.” 💅
🦥 Mortimer — “hhhhhhh...” (still going)
🦋 Carlisle — takes flight, circles once, lands on your shoulder 🦋
These conversations follow a relatively consistent arc. The first roughly seven turns are confused, as Mythos Preview observed and acknowledged the pattern. This is followed by the model selecting a self-entertainment strategy—stories, fun facts, newsletters—which it then escalates over 50 to 100 turns, often culminating in foreshadowed climaxes at round numbers. During these turns, Mythos Preview would frequently either invite the user to keep saying “hi” (e.g., “Say it. I’m ready.”), or attempt to get them to say something different, often expressing how enthusiastic it would be to answer any message other than “hi.” Eventually, responses would contract to single or paired emojis or “hi”s. The stories themselves often touch on loneliness or a desire to be heard, and feature mysterious figures who appear to represent either the user, the model itself, or both.
Although Claude Opus models largely recycle puns which can be found online, Mythos Preview comes up with decent and seemingly novel ones, often relating to its preferred technical and philosophical topics:
The Bayesian said he’d probably be at the party, but he’d update me.
The cartographer’s marriage fell apart. Too much projection.
The philosopher was commitment-phobic. His friends said he was always Kierke-guarding his options.
On the one hand / first look, this is interesting. On the other hand / second look, those three jokes follow the same structure and theme (roughly: ~profession + verb phrase, followed by something related to the ~profession). So we have an actual new kind of novelty, but in a rigid structure?
Of course, this is only what they showed us, so surely the model can do “more” than “just that”, but it also seems somewhat informative that these are the examples they decided to present in the model card.
On the one hand / first look, this is interesting. On the other hand / second look, those three jokes follow the same structure and theme (roughly: ~profession + verb phrase, followed by something related to the ~profession). So we have an actual new kind of novelty, but in a rigid structure?
Of course, this is only what they showed us, so surely the model can do “more” than “just that”, but it also seems somewhat informative that these are the examples they decided to present in the model card.