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Practice

The Unit of Understanding Prompts in Generative AI: Token

A token is the smallest unit of text that an AI processes, which includes words, punctuation, numbers, and more.

Reference: How Generative AI Understands Prompts

AI models like ChatGPT process text on a token basis, enabling them to understand and generate sentences.

For example, the sentence Hello, my name is CodeFriends! is tokenized as follows:

Example of Tokenizing a Sentence
- Hello
- ,
- my
- name
- is
- Code
- Friends
- !

The AI model understands the relationships between these tokens statistically, and based on the input prompt, generates new text.


Cost Calculation Structure of Generative AI Models​

Generative AI calculates costs considering both input tokens to understand the prompt and output tokens to generate responses.

For example, let's assume a model's cost structure is $0.002 per 1,000 tokens.

If an AI needs 400 tokens to understand a prompt and 1,100 tokens to generate a response, the total cost is calculated as follows:

  • Input tokens: 400 tokens x $0.002 / 1,000 tokens = $0.0008

  • Output tokens: 1,100 tokens x $0.002 / 1,000 tokens = $0.0022

Therefore, the total cost is $0.0008 (input) + $0.0022 (output) = $0.003.


Writing Prompts to Reduce Costs​

To reduce the number of tokens required for the desired response, it's beneficial to write prompts as follows:

Generally, more tokens are used for output than input, so optimizing for output tokens is especially important.

  1. Control Output Length: Limit the length of the AI's response to ensure it includes only the necessary information.
Example of Controlling Output Length
Please explain the reasons for the global acceleration of low birth rates within 200 characters.
  1. Specify Answer Format: Without a specified format, AI may generate responses longer than desired. Therefore, providing a preferred format with examples is advisable.
Example with Answer Format Provided
Explain the reasons for the global acceleration of low birth rates using the format below:

1. Economic factors: [within 100 characters]

2. Social change factors: [within 100 characters]

3. Policy factors: [within 100 characters]

Practice​

Send prompt examples and compare the AI's responses.

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