Tutorial 1: Build Your First Pipeline

Learn the basics by building a simple LLM application.

Time: 15 minutes
Level: Beginner

What You’ll Build

A command-line application that sends prompts to an LLM and displays responses.

What You’ll Learn

Create a pipeline
Configure an LLM provider
Execute requests
Handle responses
Track costs

Prerequisites

Go 1.21+
OpenAI API key (get one at platform.openai.com)

Step 1: Set Up Your Project

Create a new Go module:

mkdir my-llm-app
cd my-llm-app
go mod init my-llm-app

Install PromptKit:

go get github.com/AltairaLabs/PromptKit/runtime@latest

Step 2: Set Your API Key

Export your OpenAI API key:

export OPENAI_API_KEY="sk-..."

Step 3: Create Your First Pipeline

Create main.go:

package main

import (
    "context"
    "fmt"
    "log"
    "os"
    
    "github.com/AltairaLabs/PromptKit/runtime/pipeline"
    "github.com/AltairaLabs/PromptKit/runtime/pipeline/middleware"
    "github.com/AltairaLabs/PromptKit/runtime/providers/openai"
)

func main() {
    // Step 1: Create provider
    provider := openai.NewOpenAIProvider(
        "openai",
        "gpt-4o-mini",
        os.Getenv("OPENAI_API_KEY"),
        openai.DefaultProviderDefaults(),
        false,
    )
    defer provider.Close()
    
    // Step 2: Build pipeline
    pipe := pipeline.NewPipeline(
        middleware.ProviderMiddleware(provider, nil, nil, &middleware.ProviderMiddlewareConfig{
            MaxTokens:   500,
            Temperature: 0.7,
        }),
    )
    defer pipe.Shutdown(context.Background())
    
    // Step 3: Execute request
    ctx := context.Background()
    result, err := pipe.Execute(ctx, "user", "What is artificial intelligence?")
    if err != nil {
        log.Fatal(err)
    }
    
    // Step 4: Display response
    fmt.Printf("Response: %s\n", result.Response.Content)
    fmt.Printf("Tokens: %d\n", result.Response.Usage.TotalTokens)
    fmt.Printf("Cost: $%.6f\n", result.Cost.TotalCost)
}

Step 4: Run Your Application

go run main.go

You should see output like:

Response: Artificial intelligence (AI) refers to the simulation of human intelligence...
Tokens: 152
Cost: $0.000023

Understanding the Code

1. Create Provider

provider := openai.NewOpenAIProvider(
    "openai",           // Provider name
    "gpt-4o-mini",      // Model (cost-effective)
    os.Getenv("OPENAI_API_KEY"),  // API key
    openai.DefaultProviderDefaults(),  // Default settings
    false,              // Debug mode off
)

The provider connects to OpenAI’s API. We use gpt-4o-mini for cost-effectiveness.

2. Build Pipeline

pipe := pipeline.NewPipeline(
    middleware.ProviderMiddleware(provider, nil, nil, config),
)

The pipeline processes requests through middleware. ProviderMiddleware sends requests to the LLM.

3. Execute Request

result, err := pipe.Execute(ctx, "user", "What is artificial intelligence?")

Execute() takes:

Context for cancellation
Role ("user" for user messages)
Content (your prompt)

4. Handle Response

fmt.Printf("Response: %s\n", result.Response.Content)
fmt.Printf("Tokens: %d\n", result.Response.Usage.TotalTokens)
fmt.Printf("Cost: $%.6f\n", result.Cost.TotalCost)

The result contains:

Response.Content: LLM’s response text
Response.Usage: Token counts
Cost.TotalCost: Cost in dollars

Experiment

Try modifying your application:

1. Change the Model

Use a more powerful model:

provider := openai.NewOpenAIProvider(
    "openai",
    "gpt-4o",  // More capable, higher cost
    os.Getenv("OPENAI_API_KEY"),
    openai.DefaultProviderDefaults(),
    false,
)

2. Adjust Temperature

Make responses more creative:

config := &middleware.ProviderMiddlewareConfig{
    MaxTokens:   500,
    Temperature: 1.0,  // More creative (0.0 = deterministic, 2.0 = very creative)
}

3. Limit Response Length

Reduce costs by limiting tokens:

config := &middleware.ProviderMiddlewareConfig{
    MaxTokens:   100,  // Shorter responses
    Temperature: 0.7,
}

4. Multiple Questions

Ask several questions:

questions := []string{
    "What is AI?",
    "What is machine learning?",
    "What is deep learning?",
}

for _, question := range questions {
    result, err := pipe.Execute(ctx, "user", question)
    if err != nil {
        log.Printf("Error: %v\n", err)
        continue
    }
    
    fmt.Printf("\nQ: %s\n", question)
    fmt.Printf("A: %s\n", result.Response.Content)
    fmt.Printf("Cost: $%.6f\n\n", result.Cost.TotalCost)
}

Common Issues

”authentication failed”

Problem: Invalid API key.

Solution: Check your API key is set:

echo $OPENAI_API_KEY

“context deadline exceeded”

Problem: Request took too long.

Solution: Increase timeout:

ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
defer cancel()

High costs

Problem: Using expensive model or many tokens.

Solution:

Use gpt-4o-mini instead of gpt-4o
Reduce MaxTokens to 100-300
Monitor costs with result.Cost.TotalCost

Complete Example

Here’s the full application with better structure:

package main

import (
    "context"
    "fmt"
    "log"
    "os"
    "time"
    
    "github.com/AltairaLabs/PromptKit/runtime/pipeline"
    "github.com/AltairaLabs/PromptKit/runtime/pipeline/middleware"
    "github.com/AltairaLabs/PromptKit/runtime/providers/openai"
)

func main() {
    // Validate API key
    apiKey := os.Getenv("OPENAI_API_KEY")
    if apiKey == "" {
        log.Fatal("OPENAI_API_KEY environment variable not set")
    }
    
    // Create provider
    provider := openai.NewOpenAIProvider(
        "openai",
        "gpt-4o-mini",
        apiKey,
        openai.DefaultProviderDefaults(),
        false,
    )
    defer provider.Close()
    
    // Build pipeline
    config := &middleware.ProviderMiddlewareConfig{
        MaxTokens:   500,
        Temperature: 0.7,
    }
    
    pipe := pipeline.NewPipeline(
        middleware.ProviderMiddleware(provider, nil, nil, config),
    )
    defer pipe.Shutdown(context.Background())
    
    // Create context with timeout
    ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
    defer cancel()
    
    // Get prompt from command line or use default
    prompt := "What is artificial intelligence?"
    if len(os.Args) > 1 {
        prompt = os.Args[1]
    }
    
    // Execute request
    fmt.Printf("Prompt: %s\n\n", prompt)
    result, err := pipe.Execute(ctx, "user", prompt)
    if err != nil {
        log.Fatalf("Request failed: %v", err)
    }
    
    // Display results
    fmt.Printf("Response:\n%s\n\n", result.Response.Content)
    fmt.Printf("--- Metrics ---\n")
    fmt.Printf("Input tokens:  %d\n", result.Response.Usage.PromptTokens)
    fmt.Printf("Output tokens: %d\n", result.Response.Usage.CompletionTokens)
    fmt.Printf("Total tokens:  %d\n", result.Response.Usage.TotalTokens)
    fmt.Printf("Cost:          $%.6f\n", result.Cost.TotalCost)
}

Run with custom prompt:

go run main.go "Explain quantum computing in simple terms"

What You’ve Learned

✅ Create and configure a pipeline
✅ Connect to an LLM provider
✅ Execute basic requests
✅ Handle responses
✅ Track token usage and costs
✅ Adjust model parameters

Next Steps

Continue to Tutorial 2: Multi-Turn Conversations to add conversation state and build a chatbot.