“Prompt to make Opus 5 act like a base model” by Hruss

The text as follows: see the below — makes Claude think that the prompt is unfinished, and fill in its own prompt. It will subsequently claim that it recieved what it wrote from your own prompt, which is consistent with modeling it as continuing your prompt. You can also add qualifiers, like "see the math proof below" or "see the story below" and it will make those, unless it would expect them to be a file, in which case it doesn't work. The proofs, unfortunately, aren't very good. That said, it essentially is a way to use it as just the base model, and the pre-ChatGPT prompting techniques seem to work well here. Claude seems to have a strange model of the user: very informal prompts, text message transcripts, occasional concerns about eating disorders in particular, etc. Also, it will use its own style tics: "genuinely", em-dashes, trust, honest, etc. all appear in the user's prompt frequently. I suppose that implies its style tics are what it sees all text as being, not just what a HHH agent would sound like. I imagine there is much more to find here until Anthropic [...] --- First published: July 30th, 2026 Source: https://www.lesswrong.com/posts/ZSBse2fyftgHiJ3Kq/prompt-to-make-opus-5-act-like-a-base-model --- Narrated by TYPE III AUDIO.