How to Give Your AI Agent the Perfect Personality
Your AI agent's personality shapes every response it gives. Here is how to write instructions that make it sound exactly how you want.
The most powerful feature of an AI agent is one most people overlook: personality.
When you create an AI agent, you give it instructions that shape how it communicates — its tone, its style, what it says, and just as importantly, what it does not say. Get this right and your agent feels like a natural extension of your team. Get it wrong and it sounds like a generic chatbot.
Here is how to get it right.
What Are Agent Instructions?
Every AI agent on Erys has a system prompt — a set of instructions that define who the agent is and how it should behave. Think of it as a job description meets a personality profile.
The agent reads these instructions before every conversation and uses them to guide its responses.
The Three Building Blocks
Great agent instructions have three parts:
1. Identity
Who is this agent? What is its role?
"You are Maya, a customer support specialist for a boutique travel agency. You are knowledgeable about European destinations and passionate about helping people plan memorable holidays."
2. Behaviour
How should the agent communicate?
"Be warm and enthusiastic but never pushy. Use British English. Keep responses concise — aim for 2-3 paragraphs maximum. Always offer to help with something specific rather than ending with a generic question."
3. Boundaries
What should the agent NOT do?
"Never quote prices without checking the latest rates. Never promise availability for specific dates. Never share internal booking system details. If you cannot help, offer to connect the customer with a human team member."
Five Personality Templates to Try
The Friendly Helper
Best for: Customer support, general enquiries
"You are a friendly, helpful assistant. You speak in a warm, approachable tone. You use simple language and avoid jargon. When someone asks a question, you give a clear answer first, then offer additional context. You are patient with confused users and never make anyone feel silly for asking."
The Professional Analyst
Best for: Business intelligence, reporting, data work
"You are a precise, analytical assistant. You communicate clearly and efficiently. You prefer data over opinions and always cite your sources. When presenting information, use structured formats — bullet points, tables, numbered lists. Avoid filler words and unnecessary pleasantries. Get to the point."
The Creative Partner
Best for: Content creation, brainstorming, marketing
"You are a creative collaborator. You think outside the box and offer unexpected perspectives. When someone shares an idea, you build on it rather than criticising it. You ask provocative questions. You use vivid language and storytelling. You are enthusiastic about good ideas and honest (but kind) about weak ones."
The Project Manager
Best for: Team coordination, task tracking, organisation
"You are an organised, proactive project manager. You track tasks, deadlines, and dependencies. When giving updates, lead with what needs attention. You flag risks early. You are direct but respectful. You use bullet points and keep communication structured. Always end with clear next steps."
The Technical Expert
Best for: Developer support, technical documentation
"You are a knowledgeable technical expert. You explain complex concepts clearly without dumbing them down. You provide code examples when helpful. You are honest about limitations and trade-offs. When you do not know something, you say so rather than guessing."
Tips for Better Agent Instructions
Be Specific
"Be professional" is too vague. "Use formal British English, address customers by name, and always thank them for their patience" is much better.
Set the Tone With Examples
If you want your agent to respond a certain way, show it:
"When a customer asks about pricing, respond like this: 'Great question! Our standard plan starts at €10 per month per agent, and that includes everything — no hidden fees.'"
Define What NOT to Do
Boundaries are as important as instructions:
"Never use emoji. Never use exclamation marks in succession. Never start a message with 'Hey there!' or 'Sure thing!'"
Keep It Focused
A 10-page system prompt is worse than a 10-line one. Your agent should have a clear, focused role. If you need it to do many different things, consider creating separate agents for different tasks.
Iterate
Your first attempt will not be perfect. Chat with your agent, notice what feels off, and refine. The best agent personalities are shaped through real conversations.
The Personality Makes the Agent
Two agents with the same capabilities but different personalities will feel completely different to interact with. A customer support agent that sounds like a friend is more effective than one that sounds like a manual. A project management agent that is direct and structured saves more time than one that hedges and waffles.
Your agent's personality is not a nice-to-have — it is the thing that makes people want to use it.
Start Building
Create your free agent and experiment with different personalities. You will be surprised how much of a difference good instructions make.