Message roles (system, user, assistant) in Prompt Engineering / GenAI - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the role of the system message in a conversation with an AI?

The system message sets the overall behavior and rules for the AI. It guides how the AI should respond throughout the conversation.

beginner

Who sends the user message in an AI chat?

The user message is sent by the person interacting with the AI. It contains questions, commands, or information for the AI to respond to.

beginner

What does the assistant message represent in AI conversations?

The assistant message is the AI's reply to the user. It provides answers, explanations, or actions based on the user's input and system instructions.

intermediate

Why is the system message important before user and assistant messages?

Because it sets the context and rules, the system message helps the AI understand how to behave, making the conversation more useful and consistent.

intermediate

Can the assistant message influence the next user message?

Yes, the assistant's reply can guide or change what the user asks next, shaping the flow of the conversation.

Which message role sets the AI's behavior and rules?

A System

B User

C Assistant

D Observer

The system message defines the AI's behavior and rules for the conversation.

Who sends the user message in an AI chat?

A The person interacting with the AI

B The system

C The AI assistant

D The developer

The user message is sent by the person interacting with the AI.

What does the assistant message contain?

A Instructions for the AI

B System logs

C User questions

D AI's replies

The assistant message contains the AI's replies to the user.

Why is the system message placed before user and assistant messages?

A To log the conversation

B To greet the user

C To set context and rules for the AI

D To end the chat

The system message sets the context and rules for the AI's behavior.

Can the assistant message affect what the user asks next?

A No, user messages are independent

B Yes, it can guide the user's next input

C Only if the system allows it

D Only in multi-user chats

The assistant's reply can influence the user's next question or command.

Explain the roles of system, user, and assistant messages in an AI conversation.

Think about who sends each message and what its purpose is.

Why is the system message important before the user and assistant messages?

Consider how the AI knows how to behave.

Practice

1. What is the main purpose of the system role in AI chat messages?

easy

A. To store conversation history

B. To provide user input or questions

C. To set instructions and guide the AI's behavior

D. To display the AI's answers

Solution

1. Step 1: Understand the roles in AI chat

   The system role is designed to give the AI instructions or context on how to respond.

2. Step 2: Differentiate from other roles

   The user role is for input, and the assistant role is for AI output, so setting instructions fits the system role.

3. Final Answer:

   To set instructions and guide the AI's behavior -> Option C

4. Quick Check:

   System role = instructions [OK]

Hint: System role sets AI instructions, user inputs, assistant replies [OK]

Common Mistakes:

• Confusing system role with user input
• Thinking assistant role sets instructions
• Assuming system role stores chat history

2. Which of the following is the correct way to represent a user message in a chat API call?

easy

A. {"role": "assistant", "content": "Hello!"}

B. {"role": "user", "content": "What is AI?"}

C. {"role": "system", "content": "You are helpful."}

D. {"role": "bot", "content": "I can help."}

Solution

1. Step 1: Identify the role for user input

   The user messages must have the role set to "user" to indicate input from the person.

2. Step 2: Check each option's role field

   {"role": "user", "content": "What is AI?"} uses "user" correctly, while others use "assistant", "system", or invalid "bot".

3. Final Answer:

   {"role": "user", "content": "What is AI?"} -> Option B

4. Quick Check:

   User role = "user" [OK]

Hint: User messages always have role "user" in JSON [OK]

Common Mistakes:

• Using "bot" instead of "assistant" or "user"
• Mixing system role with user messages
• Forgetting to set the role field

3. Given this message list sent to an AI model:

[{"role": "system", "content": "You are a helpful assistant."}, {"role": "user", "content": "Hello!"}]

What role will the AI use to respond?

medium

A. system

B. user

C. moderator

D. assistant

Solution

1. Step 1: Understand message roles in conversation

   The AI responds with messages having the role "assistant" to show its output.

2. Step 2: Identify the role for AI replies

   Since the input messages include system and user roles, the AI's reply will be labeled as "assistant".

3. Final Answer:

   assistant -> Option D

4. Quick Check:

   AI replies use role "assistant" [OK]

Hint: AI responses always have role "assistant" [OK]

Common Mistakes:

• Thinking AI replies use "system" role
• Confusing user input role with AI output
• Assuming unknown roles like "moderator"

4. You wrote this message list for an AI chat:

[{"role": "system", "content": "Be concise."}, {"role": "user", "content": "Explain AI."}, {"role": "user", "content": "Tell me more."}]

Why might the AI ignore the second user message?

medium

A. Because there are two user messages without an assistant reply in between

B. Because the system role is missing

C. Because the assistant role is used twice

D. Because the user messages are empty

Solution

1. Step 1: Check message sequence rules

   AI expects alternating user and assistant messages; two user messages in a row can cause confusion.

2. Step 2: Identify the problem in the message list

   Here, two user messages come one after another without an assistant reply, so the AI may ignore the second user message.

3. Final Answer:

   Because there are two user messages without an assistant reply in between -> Option A

4. Quick Check:

   Messages alternate user-assistant-user [OK]

Hint: User and assistant messages must alternate to avoid ignored inputs [OK]

Common Mistakes:

• Thinking system role is missing
• Assuming assistant role used twice
• Believing empty messages cause ignoring

5. You want the AI to act as a friendly tutor and answer questions clearly. Which message list correctly sets this up before the user asks a question?

hard

A. [{"role": "system", "content": "You are a friendly tutor. Answer clearly."}, {"role": "user", "content": "Explain math."}]

B. [{"role": "user", "content": "Explain math."}, {"role": "system", "content": "Be friendly and clear."}]

C. [{"role": "assistant", "content": "I will be friendly."}, {"role": "user", "content": "Explain math."}]

D. [{"role": "user", "content": "Explain math."}, {"role": "assistant", "content": "I will be friendly."}]

Solution

1. Step 1: Place instructions in the system role

   Instructions for AI behavior must be in the system message before user input.

2. Step 2: Check message order and roles

   [{"role": "system", "content": "You are a friendly tutor. Answer clearly."}, {"role": "user", "content": "Explain math."}] correctly puts the system message first with instructions, then the user question.

3. Final Answer:

   [{"role": "system", "content": "You are a friendly tutor. Answer clearly."}, {"role": "user", "content": "Explain math."}] -> Option A

4. Quick Check:

   System message first with instructions [OK]

Hint: Put AI instructions in system role before user messages [OK]

Common Mistakes:

• Putting system message after user input
• Using assistant role for instructions
• Starting with user message without system context