Generative AI is one of the features of Code Assist. If you have any ethical or legal concerns, you can use Code Assist without this feature by disabling generative AI in the options.

To use generative AI with your comments:
* Type "//gpt "
* Type your prompt
* Press Enter key

To use generative AI with CodeLens:
* Click Gpt Codelens which is above class or method declaration

Requirements (OpenAI ChatGPT): You need an OpenAI account and provide it's API key to this asset.
https://platform.openai.com/account/api-keys

Provide key by one of the below
* Create an environment variable called OPENAI_API_KEY with the API key
* Create a file with name .openai under user profile directory with the API key
* Set API key in Visual Studio options, Tools->Options->Unity Code Assist->Generative AI->Authentication

Requirements (Google Gemini): You need a Google account and provide it's API key to this asset.
https://ai.google.dev/gemini-api/docs/api-key

Provide key by one of the below
* Create an environment variable called GOOGLE_API_KEY with the API key
* Create a file with name .gemini under user profile directory with the API key
* Set API key in options, Tools->Options->Unity Code Assist->Generative AI->Authentication

Requirements (Anthropic Claude): You need an Anthropic account and provide it's API key to this asset.
https://console.anthropic.com/settings/keys

Provide key by one of the below
* Create an environment variable called ANTHROPIC_API_KEY with the API key
* Create a file with name .anthropic under user profile directory with the API key
* Set API key in options, Tools->Options->Comment2GPT->Authentication

Requirements (DeepSeek): You need a DeepSeek account and provide it's API key to this asset.
https://platform.deepseek.com/api_keys

Provide key by one of the below
* Create an environment variable called DEEPSEEK_API_KEY with the API key
* Create a file with name .deepseek under user profile directory with the API key
* Set API key in options, Tools->Options->Comment2GPT->Authentication

This asset has one-time purchase fee, but you may need to pay extra for OpenAI, Google AI, Anthropic or DeepSeek services to use Generative AI feature.
https://openai.com/pricing
https://ai.google.dev/pricing
https://www.anthropic.com/pricing#anthropic-api
https://api-docs.deepseek.com/quick_start/pricing