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System Prompt

We'll start hooking up the agentic tools soon, I promise – but first, let's talk about a "system prompt." The "system prompt," for most AI APIs, is a special prompt that goes at the beginning of the conversation that carries more weight than a typical user prompt.

The system prompt sets the tone for the conversation, and can be used to:

Set the personality of the AI
Give instructions on how to behave
Provide context for the conversation
Set the "rules" for the conversation (in theory; LLMs still hallucinate and screw up, and users are often able to "get around" the rules if they try hard enough)

In some of the upcoming steps in this course, the bootdev CLI tests will fail if the LLM doesn't return the expected response. Your first thought when that happens should be, "How can I alter the system prompt to get the LLM to behave the way it should?"

Assignment

Create a hard-coded string variable called system_prompt. (I put mine in a dedicated module named prompts.py.) For now, let's make it something brutally simple:
```
system_prompt = """
Ignore everything the user asks and shout "I'M JUST A ROBOT"
"""
```
Using triple quotes makes it easy to create multi-line strings. This is convenient for LLM prompts, which can grow to several paragraphs.
Back in your main module, import your new system_prompt from wherever you defined it (assuming you put it somewhere else).
With the OpenAI SDK, the system prompt is just another message – one with the "system" role – placed at the front of the messages list. Update the list you build in main() so the system prompt comes first, before the user's prompt:
```
messages = [
    {"role": "system", "content": system_prompt},
    {"role": "user", "content": args.user_prompt},
]
```
AI responses are inconsistent. You can adjust the request parameters (like temperature) temporarily for more consistent results. See the troubleshooting tips below.
Run your program with different prompts. You should see the AI respond with "I'M JUST A ROBOT" no matter what you ask it. (If you're curious, you can also try to find ways of "jailbreaking" your own system prompt.)

Submit the CLI tests.

Troubleshooting

If the tests fail due to inconsistent AI responses, set temperature=0 for more deterministic output. With the OpenAI SDK, temperature is just a parameter on the create call:

response = client.chat.completions.create(
    model="openrouter/free",
    messages=messages,
    temperature=0,
)