API Reference

API Reference

Client Methods

Initialization

ChatGPT::Client.new(api_key = nil)

Creates a new client instance. If api_key is nil, uses the configured global API key.

Chat API (Recommended)

Chat Completion

client.chat(messages, params = {})

Parameters:

• messages: Array of message hashes with role and content
• params: Optional parameters hash

# Example usage
response = client.chat([
  { role: "user", content: "What is Ruby?" }
])
puts response.dig("choices", 0, "message", "content")

# With parameters
response = client.chat([
  { role: "system", content: "You are a helpful assistant." },
  { role: "user", content: "What is Ruby?" }
], {
  model: 'gpt-3.5-turbo',  # Optional, defaults to configured value
  temperature: 0.7,        # Optional, defaults to 0.5
  max_tokens: 100,         # Optional, defaults to 16
  top_p: 1.0,             # Optional
  n: 1                     # Optional, number of responses
})

Streaming Chat

client.chat_stream(messages, params = {}) { |chunk| ... }

Same parameters as chat, but requires a block for handling chunks.

# Example usage
client.chat_stream([
  { role: "user", content: "Tell me a story" }
]) do |chunk|
  print chunk.dig("choices", 0, "delta", "content")
end

Completions API

Text Completion

client.completions(prompt, params = {})

Parameters:

• prompt: String prompt for completion
• params: Optional parameters hash

# Example usage
response = client.completions("Write a haiku about Ruby")
puts response.dig("choices", 0, "text")

# With parameters
response = client.completions(
  "Write a haiku about Ruby",
  {
    engine: 'gpt-3.5-turbo-instruct',  # Optional, defaults to configured value
    max_tokens: 50,                    # Optional
    temperature: 0.7,                  # Optional
    top_p: 0.9,                       # Optional
    n: 1                              # Optional
  }
)

Model Compatibility

API Method	Compatible Models	Response Access
Chat	gpt-4, gpt-3.5-turbo	response.dig("choices", 0, "message", "content")
Completions	gpt-3.5-turbo-instruct	response.dig("choices", 0, "text")

Configuration Options

# For Chat API (Recommended)
ChatGPT.configure do |config|
  config.api_key = ENV['OPENAI_API_KEY']
  config.api_version = 'v1'
  config.default_engine = 'gpt-3.5-turbo'  # For chat
  config.request_timeout = 30
  config.max_retries = 3
  config.default_parameters = {
    max_tokens: 16,
    temperature: 0.5,
    top_p: 1.0,
    n: 1
  }
end

# For Completions API
ChatGPT.configure do |config|
  config.api_key = ENV['OPENAI_API_KEY']
  config.api_version = 'v1'
  config.default_engine = 'gpt-3.5-turbo-instruct'  # For completions
  # ... other config remains same
end

Response Formats

Chat Response

{
  "choices" => [{
    "message" => {
      "role" => "assistant",
      "content" => "Response content here"
    }
  }]
}

Completions Response

{
  "choices" => [{
    "text" => "Completion text here"
  }]
}