What LLM Should I Choose for My AI Agent?

Regal offers multiple leading Large Language Models (LLMs) to power your AI agents for phone and SMS conversations. Each is optimized for different use cases—so the best choice depends on your goals, call type, complexity of conversation, and cost tolerance. 

We recommend starting with OpenAI GPT-4.0 mini which is Regal's base model. Only upgrade to OpenAI 4o or switch to Claude models if you find that your AI agent isn’t performing the call as well as you’d like, and you're willing to pay more.

• Use GPT-4.0 Mini for short, simple conversations
  • Examples: 
    • Confirmation
    • Collections calls
    • Qualification calls with < 7 questions
  • Pros: Fastest model, cost-effective, great for straightforward tasks/conversations. Included in Regal base AI voice agent minute pricing
  • Cons: Slightly weaker at reasoning, so if your agent has to do some math, for example don’t use this model.
    
    
• Use GPT-4.0 for longer, more complex calls or ones that require math/reasoning
  • Examples: 
    • Long qualification calls with 10+ steps or conditional steps
    • More open-ended support calls
    • Calls with many different custom actions to invoke, especially if iterative custom action calling
    • Calls that require complex reasoning, such as math (e.g., agent needs to multiply the number of rooms the customer is moving + the number of boxes to estimate a quote)
  • Pros: Handles conditional logic, multiple functions, and nuanced conversation better.
  • Cons: More expensive; adds a few hundred milliseconds of latency—but most customers won’t notice.

When to Consider Claude

If you’ve tried OpenAI GPT 4.0 Mini or 4.0 and they aren’t getting the performance you need—especially around memory, creativity, or edge case handling—consider:

• Claude 3.5 Haiku for fast, lightweight conversations
• Claude 3.7 Sonnet for longer, more complex conversations

Still not sure? Just reach out – we’re happy to help you tune your agent for the best performance.

Want Regal to offer a different LLM? Just reach out – we’re constantly evaluating new LLMs and happy to onboard any that demonstrate differentiated performance.

Want to bring your own LLM? Just reach out – we’ll help you incorporate it into Regal.