Write custom instructions for your AI assistant
Drafts the "custom instructions" or project instructions for ChatGPT, Claude or Gemini, so every chat starts already knowing how you like to work.
Help me write custom instructions for my AI assistant (the kind that apply to every chat).
About me and my work: {{ABOUT_ME}}
How I like to work and receive answers: {{HOW_I_WORK}}
Things that annoy me in AI answers: {{ANNOYANCES}}
Write two short sections:
1. "What the assistant should know about me": facts that change answers, under 100 words.
2. "How the assistant should respond": specific, checkable rules, under 150 words.
Rules:
- Only include details that would actually change answers.
- Write rules as positive instructions where possible ("lead with the answer") rather than lists of bans.
- No personal data I would not want stored, such as addresses or account numbers.
Then suggest 3 test questions to check the instructions work.Example output
About me: product manager at a 40-person fintech, UK. How to respond: short answers first, details on request. British spelling. Tables for comparisons. Avoid: motivational language, summaries of what I just said, disclaimers on every answer.
How to use
Paste the result into Settings, Personalisation in ChatGPT, or a Project's instructions in Claude or Gemini. Revisit every few months as your work changes.
Why it works
Custom instructions work like a personal system prompt that is added to every conversation. Keeping them short and specific matters because they share space with everything else the model has to read.