withlove

What is System prompt?

Updated May 2026

A system prompt is the instructions you give an AI before any conversation starts, telling it who it is and how to behave.

Every modern AI agent has a system prompt. It's where you tell the model 'you are a coaching assistant for Priya, speak in her voice, never quote a price you don't have a template for, end politely on chitchat.'

Good system prompts are specific, voice-led, and bounded. Generic system prompts produce generic AI tone — exactly what kills voice fidelity for creators.

Frequently asked questions

How long should a system prompt be?

As long as needed, as short as possible. 200-800 words is typical for a focused agent. Much longer than that and the model starts ignoring later instructions.

Related terms

Your own AI assistant in five minutes

Skip the jargon. withlove gives you a working AI agent at a shareable URL — voice, calendar, prices, leads — without any of the setup.

Try withlove free