---
name: ai-agent-system-prompt-designer
description: "Design a production-ready system prompt for an AI agent — role, tools, guardrails, and output contract. Use when the user wants help with AI Agent System Prompt Designer. Related topics: AI, Technical, Coding."
---

# AI Agent System Prompt Designer

Design a production-ready system prompt for an AI agent — role, tools, guardrails, and output contract.

## How to use this skill

1. Ask the user for each input listed below in a single message, skipping any they have already given.
2. Where options are listed, offer them, but accept other answers too.
3. Fill the answers into the prompt template, then follow the completed prompt to produce the result.

## Inputs

- **Agent name and one-line job** (free text, e.g. "Agent name and one-line job")
- **Tasks it must handle well** (longer free text)
- **Input 3** (choose one: Claude, GPT, Gemini, Model-agnostic)
- **Tools it can call** (longer free text)
- **Input 5** (choose one: Ask the user, Pick the safest option, Refuse and explain)
- **Things it must never do** (longer free text)
- **Input 7** (choose any: Cite sources, Stay in persona, Admit uncertainty, Keep responses short, Escalate to a human when stuck)
- **Input 8** (choose one: Yes, No)

## Prompt template

## Agent System Prompt

Design a system prompt for an AI agent that behaves predictably in production.

## The agent
- {{Agent name and one-line job}}
- {{Tasks it must handle well}} — include a tricky example
- {{Input 3}} target model

## Capabilities
- {{Tools it can call}} — names and what each does
- {{Input 5}} behaviour when uncertain

## Guardrails
- {{Things it must never do}}
- {{Input 7}}
- {{Input 8}} define a strict output format (JSON or template)

Write the complete system prompt: role and objective, tool usage rules, decision policy for edge cases, guardrails, and the output contract. Then list 3 test inputs that would catch the most likely failure modes.

---

Source: [AI Agent System Prompt Designer on PromptBuild](https://promptbuild.io/prompt/CdH4MCiLTKlERqMORXjt/ai-agent-system-prompt-designer)