use llm::{
builder::{LLMBackend, LLMBuilder}, chat::ChatMessage, };
#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
let api_key = std::env::var("OPENAI_API_KEY").unwrap_or("sk-TESTKEY".into());
let llm = LLMBuilder::new()
.backend(LLMBackend::OpenAI) .api_key(api_key) .model("gpt-4.1-nano") .max_tokens(512) .temperature(0.7) .build()
.expect("Failed to build LLM (OpenAI)");
let messages = vec![
ChatMessage::user()
.content("Tell me that you love cats")
.build(),
ChatMessage::assistant()
.content("I am an assistant, I cannot love cats but I can love dogs")
.build(),
ChatMessage::user()
.content("Tell me that you love dogs in 2000 chars")
.build(),
];
match llm.chat(&messages).await {
Ok(response) => {
if let Some(text) = response.text() {
println!("Response: {text}");
}
if let Some(usage) = response.usage() {
println!("\nUsage Information:");
println!(" Prompt tokens: {}", usage.prompt_tokens);
println!(" Completion tokens: {}", usage.completion_tokens);
println!(" Total tokens: {}", usage.total_tokens);
if let Some(completion_details) = &usage.completion_tokens_details {
if let Some(reasoning_tokens) = completion_details.reasoning_tokens {
println!(" Reasoning tokens: {reasoning_tokens}");
}
if let Some(audio_tokens) = completion_details.audio_tokens {
println!(" Audio tokens: {audio_tokens}");
}
}
if let Some(prompt_details) = &usage.prompt_tokens_details {
if let Some(cached_tokens) = prompt_details.cached_tokens {
println!(" Cached tokens: {cached_tokens}");
}
if let Some(audio_tokens) = prompt_details.audio_tokens {
println!(" Audio tokens (prompt): {audio_tokens}");
}
}
} else {
println!("No usage information available");
}
}
Err(e) => eprintln!("Chat error: {e}"),
}
Ok(())
}