I'm Bernard. I built AgentTune because every AI talks to me like I'm someone else. Custom instructions help, but "be concise" is a sticky note, not personalization. The fix turned out to be embarrassingly simple: a Markdown file describing how you think, pasted into the system prompt. So I made 43... one per personality type across MBTI, Big Five, Enneagram, DISC, and Attachment. Free. MIT. Fun finding from the research page: we ran 2,200 personality tests across six frontier models (https://agent-tune.com/research). They all came back INTJ. If Claude, ChatGPT, and Gemini have started sounding like the same person to you. Two questions I'd love feedback on: 1. Take a test, paste the file — did your AI actually reply differently after? 2. Where do you spend the most time (Claude Code, Cursor, ChatGPT, Gemini)? ^ that's where I want to nail the install experience next. Thanks for taking a look 🙏 — Bernard

AgentTune

Free personality-based tunings for your AI agent

Free personality-based tunings for your AI agent