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Prompt As Code

This page is a tutorial on creating prompt with GenAIScript. It is designed to be opened in Visual Studio Code as a Notebook.

About GenAIScript Markdown Notebooks

The GenAIScript Markdown Notebook will parse the markdown document into a Notebook view and use Visual Studio Code’s support to provide a rich editing experience. It should work with any markdown file as long as the code fence use ”```”.

  • Each JavaScript code block is an self-contained GenAIScript that can be executed individually. The results are attached to each code block and saved in the markdown file.
  • This is a stateless kernel, so the variables are not shared between code blocks.
  • Other languages are not supported in this notebook and simply ignored.

Prompt as code

GenAIScript lets you write prompts as a JavaScript program. GenAIScript runs your program; generate chat messages; then handles the remaining interaction with the LLM API.

$

Let’s start with a simple hello world program.

$`Say "hello!" in emojis`
👤 user 
Say "hello!" in emojis
🤖 assistant 
👋😃!

The $ function formats the strings and write them to the user message. This user message is added to the chat messages and sent to the LLM API. Under the snippet, you can review both the user message (that our program generated) and the assistant (LLM) response.

You can run the code block by clicking the Execute Cell button on the top left corner of the code block. It will be default try to use the openai:gpt-3.5-turbo LLM. If you need to use a different model, update the model field in the front matter at the start of the document. There are many options documented in configuration.

Once the execution is done, you will also an additional trace entry that allows you to dive in the internal details of the GenAIScript execution. This is very helpful to diagnose issues with your prompts. The trace can be quite large so it is not serialized in the markdown file.

You can use the JavaScript for loop and sequence multiple $ calls to append text to the user message. You can also inner expression to generate dynamic content.

// let's give 3 tasks to the LLM
// to get 3 different outputs
for (let i = 1; i <= 3; i++) $`- Say "hello!" in ${i} emojis.`
$`Respond with a markdown list`
👤 user 
-   Say "hello!" in 1 emojis.
-   Say "hello!" in 2 emojis.
-   Say "hello!" in 3 emojis.
    Respond with a markdown list
🤖 assistant 
-   👋
-   👋😊
-   👋✨😃

To recap, the GenAIScript runs and generates a user messages; that gets sent to the LLM. You can review the user message (and others) in the trace.

def and env.files

The def function lets you declare and assign LLM variables. The concept of variable is most useful to import context data, in particular files, and refer to them in the rest of the prompt.

def("FILE", env.files)
$`Summarize FILE in one short sentence. Respond as plain text.`
👤 user 
FILE:


```md file="src/samples/markdown.md"
---
title: What is Markdown? - Understanding Markdown Syntax
description: Learn about Markdown, a lightweight markup language for formatting plain text, its syntax, and how it differs from WYSIWYG editors.
keywords: Markdown, markup language, formatting, plain text, syntax
sidebar: mydoc_sidebar
---


What is Markdown?
Markdown is a lightweight markup language that you can use to add formatting elements to plaintext text documents. Created by John Gruber in 2004, Markdown is now one of the world’s most popular markup languages.


Using Markdown is different than using a WYSIWYG editor. In an application like Microsoft Word, you click buttons to format words and phrases, and the changes are visible immediately. Markdown isn’t like that. When you create a Markdown-formatted file, you add Markdown syntax to the text to indicate which words and phrases should look different.


For example, to denote a heading, you add a number sign before it (e.g., # Heading One). Or to make a phrase bold, you add two asterisks before and after it (e.g., **this text is bold**). It may take a while to get used to seeing Markdown syntax in your text, especially if you’re accustomed to WYSIWYG applications. The screenshot below shows a Markdown file displayed in the Visual Studio Code text editor....
```


Summarize FILE in one short sentence. Respond as plain text.
🤖 assistant 
Markdown is a lightweight markup language for formatting plain text, using syntax to indicate formatting elements.

In GenAIScript, the env.files variable contains the list of files in context, which can be determined by a user selection in the UI, CLI arguments, or pre-configured like in this script. You can change the files in env.files by editing the files field in the front matter at the start of the document.

Filtering

When using GenAIScript from the user interface, it is common to apply a script to an entire folder. This means that you’ll get a bunch of files in env.files including some unneeded ones. The def function provides various options to filter the files, like the endsWith option.

def also provides maxTokens which will trim the content size to a number of tokens. LLM context is finite!

script({ files: "src/samples/**" }) // glob all files under src/samples
def("FILE", env.files, { endsWith: ".md", maxTokens: 1000 }) // only consider markdown files
$`Summarize FILE in one short sentence. Respond as plain text.`
👤 user 
FILE:


```md file="src/samples/markdown.md"
---
title: What is Markdown? - Understanding Markdown Syntax
description: Learn about Markdown, a lightweight markup language for formatting plain text, its syntax, and how it differs from WYSIWYG editors.
keywords: Markdown, markup language, formatting, plain text, syntax
sidebar: mydoc_sidebar
---


What is Markdown?
Markdown is a lightweight markup language that you can use to add formatting elements to plaintext text documents. Created by John Gruber in 2004, Markdown is now one of the world’s most popular markup languages.


Using Markdown is different than using a WYSIWYG editor. In an application like Microsoft Word, you click buttons to format words and phrases, and the changes are visible immediately. Markdown isn’t like that. When you create a Markdown-formatted file, you add Markdown syntax to the text to indicate which words and phrases should look different.


For example, to denote a heading, you add a number sign before it (e.g., # Heading One). Or to make a phrase bold, you add two asterisks before and after it (e.g., **this text is bold**). It may take a while to get used to seeing Markdown syntax in your text, especially if you’re accustomed to WYSIWYG applications. The screenshot below shows a Markdown file displayed in the Visual Studio Code text editor....
```


Summarize FILE in one short sentence. Respond as plain text.
🤖 assistant 
Markdown is a lightweight markup language for formatting plaintext documents, different from WYSIWYG editors.