> ## Documentation Index
> Fetch the complete documentation index at: https://docs.arcbeam.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Model Selection

> Choosing the right AI model for your needs

**Model selection** is about choosing which AI "brain" to use for different tasks. Just like you wouldn't use a calculator for writing an essay, different AI models are better suited for different jobs.

<Note>
  Each AI model has trade-offs in terms of quality, speed, and cost. The key is finding the right balance for your use case.
</Note>

## Understanding AI Models

<CardGroup cols={3}>
  <Card title="Basic Models" icon="robot">
    Smart assistants who can handle routine questions
  </Card>

  <Card title="Advanced Models" icon="brain">
    Subject matter experts who can tackle complex problems
  </Card>

  <Card title="Specialized Models" icon="wrench">
    Specialists trained for specific tasks
  </Card>
</CardGroup>

## Popular AI Model Providers

The major AI model providers offer a range of models with different capabilities and price points:

<Tabs>
  <Tab title="OpenAI (ChatGPT)" icon="openai">
    The company behind ChatGPT offers models ranging from the premium GPT-4o to the cost-effective GPT-4o mini. Known for strong general-purpose performance.

    **Visit:** [OpenAI Platform](https://platform.openai.com/docs/models)
  </Tab>

  <Tab title="Anthropic (Claude)" icon="message-bot">
    Known for following instructions well and handling longer conversations. Offers models from Claude Sonnet 4.5 (premium) to Claude Haiku 4.5 (fast & affordable).

    **Visit:** [Anthropic Models](https://docs.anthropic.com/en/docs/models-overview)
  </Tab>

  <Tab title="Google (Gemini)" icon="google">
    Can handle extremely long conversations and documents with large context windows. Latest models include Gemini 3 Flash and Gemini 2.0 Pro.

    **Visit:** [Gemini API](https://ai.google.dev/gemini-api/docs/models)
  </Tab>

  <Tab title="Open Source Models" icon="code-branch">
    Models you can run on your own servers offer complete data privacy and control, but require technical setup and infrastructure management.

    **Popular Models:**

    * **Llama** - Meta's open-source models
    * **Mixtral** - Mistral AI's mixture-of-experts models
    * **Qwen** - Alibaba's Qwen series

    **Benefits:** Complete data privacy, no per-request costs, full customization
    **Tradeoffs:** Requires infrastructure, technical expertise, and maintenance

    **Visit:** [Hugging Face Models](https://huggingface.co/models)
  </Tab>
</Tabs>

<Info>
  **Model selection changes frequently.** Visit the provider documentation above for the latest models, pricing, and capabilities. Use [evaluations](/v0/core-concepts/evaluations) to test which models work best for your specific use case.
</Info>

## How to Choose the Right Model

### Consider What You Need

| Use Case                      | What to Choose                                     | Example                                                              | Recommended Models                                         |
| ----------------------------- | -------------------------------------------------- | -------------------------------------------------------------------- | ---------------------------------------------------------- |
| **Simple, High-Volume Tasks** | Cheaper, faster models                             | Answering basic FAQs, categorizing requests                          | GPT-4o mini, Claude Haiku 4.5, or Gemini 2.0 Flash-Lite    |
| **Complex Reasoning**         | Premium models                                     | Analyzing contracts, solving complex problems                        | GPT-4o, Claude Sonnet 4.5, or Gemini 3 Flash               |
| **Very Long Documents**       | Models with large "memory"                         | Summarizing 100-page reports                                         | Gemini 2.0 Pro (2M tokens) or Gemini 2.0 Flash (1M tokens) |
| **Budget-Conscious Projects** | Most cost-effective model that meets quality needs | Start with GPT-4o mini and test if it's good enough before upgrading | Gemini 3 Flash ($0.50/$3 per 1M tokens) or GPT-4o mini     |

### The Three-Factor Balance

<Info>
  The key: Find the cheapest model that meets your quality and speed requirements.
</Info>

Every model choice involves balancing three factors:

<CardGroup cols={3}>
  <Card title="Quality" icon="star">
    * How good are the responses?
    * How often is it correct?
    * Does it understand nuance?
  </Card>

  <Card title="Speed" icon="gauge-high">
    * How fast does it respond?
    * Can users wait that long?
    * Does it meet your performance needs?
  </Card>

  <Card title="Cost" icon="dollar-sign">
    * How much does each response cost?
    * How many responses do you need per day?
    * Does it fit your budget?
  </Card>
</CardGroup>

## Common Model Selection Strategies

### Start with Mid-Tier

<Steps>
  <Step title="Start with a Balanced Model">
    Begin with a mid-tier model like GPT-4o mini that offers good quality at reasonable cost
  </Step>

  <Step title="Test with Real Questions">
    Run actual use case questions through the model to see how it performs
  </Step>

  <Step title="Upgrade Only If Needed">
    Only move to a premium model if quality isn't meeting your requirements
  </Step>

  <Step title="Downgrade If Possible">
    Only move to a cheaper model if costs are too high and quality allows
  </Step>
</Steps>

<Info>**Why this works**: 80% of tasks work fine with mid-tier models</Info>

### Use Different Models for Different Tasks

You don't need to use the same model for everything:

**Example for a customer service AI**:

<CardGroup cols={3}>
  <Card title="Simple FAQ Questions" icon="message-question">
    **Use**: Cheaper model

    **Reason**: Saves money on high volume simple tasks
  </Card>

  <Card title="Complaint Analysis" icon="triangle-exclamation">
    **Use**: Premium model

    **Reason**: Quality matters more for sensitive issues
  </Card>

  <Card title="Product Recommendations" icon="star">
    **Use**: Mid-tier model

    **Reason**: Balance of quality and cost for moderate complexity
  </Card>
</CardGroup>

### Try Before You Commit

<Steps>
  <Step title="Test with Examples">
    Test with 50-100 example questions that represent your real use case
  </Step>

  <Step title="Compare Models">
    Compare responses from different models side by side
  </Step>

  <Step title="Check All Factors">
    Evaluate quality, speed, and estimated cost for each model
  </Step>

  <Step title="Choose Based on Data">
    Make your decision based on actual test data, not assumptions
  </Step>
</Steps>

## Evaluating Model Performance

The best way to choose a model is to test it with real questions from your use case. Create 20-50 test questions that represent what users will actually ask, then compare how different models perform on accuracy, speed, and cost.

**Quick evaluation checklist**:

* Are answers accurate and complete?
* Is the tone appropriate for your use case?
* How fast does each model respond?
* What would daily costs be at your expected volume?

<Info>
  For a complete guide on evaluating models systematically, including setting up automated testing and measuring performance over time, see [Evaluations](/v0/core-concepts/evaluations).
</Info>

## Managing Models Over Time

### Track Performance

Monitor how your chosen model performs:

**Weekly checks**:

<CardGroup cols={2}>
  <Card title="User Satisfaction" icon="face-smile">
    Track user satisfaction scores and feedback
  </Card>

  <Card title="Error Rates" icon="triangle-exclamation">
    Monitor how often the model produces errors
  </Card>

  <Card title="Response Times" icon="clock">
    Ensure response times stay within acceptable range
  </Card>

  <Card title="Costs" icon="dollar-sign">
    Track actual spending against budget
  </Card>
</CardGroup>

## Cost Considerations

### Understanding Pricing

AI models typically charge per "token" (roughly 3/4 of a word):

**What affects your costs**:

<CardGroup cols={2}>
  <Card title="Input Length" icon="arrow-right-to-bracket">
    How much context you provide with each request
  </Card>

  <Card title="Output Length" icon="arrow-right-from-bracket">
    How long the AI's responses are
  </Card>

  <Card title="Volume" icon="hashtag">
    How many requests you make per day
  </Card>

  <Card title="Model Choice" icon="brain">
    Premium models cost more than standard models
  </Card>
</CardGroup>

**Example calculation**:

<Info>
  If you send 1,000 requests per day:

  * Average input: 500 words = \~650 tokens
  * Average output: 100 words = \~130 tokens
  * Using GPT-4o mini: \~\$1.50/day
  * Using GPT-4o: \~\$25/day
</Info>

### Ways to Reduce Costs

<CardGroup cols={2}>
  <Card title="Use Shorter Prompts" icon="scissors">
    Don't send unnecessary context - summarize long history instead of including everything
  </Card>

  <Card title="Limit Response Length" icon="text-size">
    If you only need a short answer, specify that - don't let the model ramble
  </Card>

  <Card title="Choose Appropriate Models" icon="filter">
    Don't use premium models for simple tasks that cheaper models can handle
  </Card>

  <Card title="Cache Common Answers" icon="database">
    For common questions, save and reuse answers to reduce duplicate processing
  </Card>
</CardGroup>

## Common Mistakes to Avoid

<CardGroup cols={2}>
  <Card title="Always Using the Most Expensive Model" icon="circle-xmark">
    **The mistake**: "We'll just use the best model for everything to ensure quality"

    **Why it's wrong**: Most tasks don't need the absolute best model. You'll spend 10x more for 5% better quality

    **Better approach**: Test if cheaper models work first. Only upgrade where quality truly matters
  </Card>

  <Card title="Switching Models Without Testing" icon="circle-xmark">
    **The mistake**: "This new model is supposed to be better, let's switch immediately"

    **Why it's wrong**: "Better" in general doesn't mean better for your specific use case

    **Better approach**: Always test with your actual questions before switching
  </Card>

  <Card title="Ignoring Speed Requirements" icon="circle-xmark">
    **The mistake**: Focusing only on quality and cost

    **Why it's wrong**: If users have to wait 10 seconds for a response, they'll leave

    **Better approach**: Define acceptable wait times upfront and only consider models that meet them
  </Card>

  <Card title="Not Monitoring Performance" icon="circle-xmark">
    **The mistake**: Choose a model once and forget about it

    **Why it's wrong**: Models, costs, and your needs all change over time

    **Better approach**: Review model performance monthly and be ready to optimize
  </Card>
</CardGroup>

## Getting Started

### Your First Model Selection

<Steps>
  <Step title="Week 1: Define Requirements">
    * What tasks will your AI handle?
    * How many requests do you expect per day?
    * What's your quality threshold?
    * What's your budget?
    * How fast do responses need to be?
  </Step>

  <Step title="Week 2: Create Test Cases">
    * Gather 30-50 real example questions
    * Define what "good" answers look like
    * Include mix of easy and hard questions
  </Step>

  <Step title="Week 3: Test Models">
    * Try 2-3 candidate models
    * Run your test questions through each
    * Measure quality, speed, and cost
    * Pick the best fit for your needs
  </Step>

  <Step title="Week 4: Launch and Monitor">
    * Start with your chosen model
    * Track real-world performance
    * Collect user feedback
    * Adjust if needed
  </Step>
</Steps>

### Questions to Ask Your Team

**Before choosing**:

<CardGroup cols={1}>
  <Card title="Question 1: Volume" icon="1">
    "How many requests will we process per day/month?"
  </Card>

  <Card title="Question 2: Budget" icon="2">
    "What's our budget for AI costs?"
  </Card>

  <Card title="Question 3: Speed" icon="3">
    "How quickly do responses need to be?"
  </Card>

  <Card title="Question 4: Quality Threshold" icon="4">
    "What happens if the quality isn't perfect?"
  </Card>

  <Card title="Question 5: Special Features" icon="5">
    "Do we need features like image understanding?"
  </Card>
</CardGroup>

**After launching**:

<CardGroup cols={1}>
  <Card title="Question 1: Actual Costs" icon="1">
    "What's our actual cost so far?"
  </Card>

  <Card title="Question 2: User Satisfaction" icon="2">
    "Are users happy with response quality?"
  </Card>

  <Card title="Question 3: Variance Analysis" icon="3">
    "How does this compare to our estimates?"
  </Card>

  <Card title="Question 4: Optimization" icon="4">
    "Should we test other models to optimize?"
  </Card>
</CardGroup>

## Next Steps

<CardGroup cols={2}>
  <Card title="Context Management" icon="message" href="/v0/core-concepts/context-management">
    Learn how to manage conversation history
  </Card>

  <Card title="Cost Optimization" icon="dollar-sign" href="/v0/core-concepts/cost-optimization">
    Strategies to reduce AI costs
  </Card>

  <Card title="Evaluations" icon="check-circle" href="/v0/core-concepts/evaluations">
    Test and measure model performance
  </Card>

  <Card title="Observability" icon="chart-line" href="/v0/core-concepts/observability">
    Monitor model performance across your system
  </Card>
</CardGroup>
