What is a system prompt?
A system prompt is the instruction that defines an AI agent's role, rules, and behaviour before any conversation begins. It sets who the agent is, what it should and should not do, and how it should respond — acting as the standing brief the model follows for every task in that role.
The system prompt is where you define an AI agent's job. Everything the agent does flows from it — its role, its limits, its tone. A vague prompt produces vague behaviour; a specific one produces a reliable, on-brief agent.
What a system prompt sets
- Role — who the agent is and what it is responsible for.
- Rules — what it must and must not do.
- Style — tone and format of responses.
- Guidance — when to use tools or ask for clarification.
System prompts in Oido
In Oido, each AI employee has its own system prompt, so you can define a distinct role per agent and reuse it across tasks. The same agent runs on whichever model provider you choose.
Frequently asked
The system prompt is the standing instruction that defines the agent's role and rules. The user prompt is the specific request in the moment. The system prompt applies to every message; the user prompt changes each turn.
Be specific about the role, the goal, the boundaries, and the desired tone. State what the agent should not do, and give examples where helpful. Clear, concrete instructions produce more reliable behaviour than vague ones.
It guides behaviour and can tell the agent when to use tools, but which tools are available is set by the agent's configuration. The prompt shapes judgment; the tool list defines capability.