Prompt Structure and Variables

Welcome to the lesson on "Prompt Structure and Variables." In this lesson, we will explore how prompts are structured and how variables are used to create dynamic and flexible AI interactions. Prompts are essential in guiding AI behavior, allowing us to tailor responses to specific needs. By the end of this lesson, you will understand how to load templates and render them using a dictionary of variables, a crucial skill in building the AI Cooking Helper.

Before we dive into templates, let's briefly recall file handling in Python. This knowledge is essential as we will be loading template files in this lesson. Remember, the open() function is used to open a file, and the read() method is used to read its contents. Here's a quick reminder:

file_path = 'example.txt'
with open(file_path, 'r') as file:
    content = file.read()
print(content)

This code snippet opens a file named example.txt, reads its contents, and prints them. The with statement ensures the file is closed automatically after reading.

Our templates represent prompts that can be enriched with variables. These templates are stored as text files with placeholders enclosed in double curly braces, like {{input}} or {{style}}. Let's look at a more flexible template example:

Rewrite the following sentence in a {{style}} tone:

Original: {{input}}

Return a list of up to 3 paraphrased versions.

In this template, {{style}} and {{input}} are placeholders. This structure allows us to inject multiple values dynamically into a single prompt.

To use a template, we first need to load it from a file. Let's break down the load_template function:

import os

def load_template(template_name):
    base_dir = os.path.abspath(os.path.join(os.path.dirname(__file__), '..'))
    prompts_dir = os.path.join(base_dir, 'static', 'prompts')
    file_path = os.path.join(prompts_dir, f"{template_name}.txt")

    with open(file_path, 'r', encoding='utf-8') as f:
        return f.read()

1. base_dir: We find the absolute path of the project root.
2. prompts_dir: We point to the specific folder where our .txt templates live.
3. file_path: We construct the full path using the template_name.
4. open: We read the file content and return it as a string.