The Engine Behind the Agent
Your OpenClaw agent is only as good as the model (LLM) powering it. In 2025, the “Big Three” have diverged significantly. Choosing the wrong model can lead to hallucinations, failed function calls, or skyrocketing costs.
1. GPT-4 Turbo (OpenAI)
The King of Function Calling.
If your agent needs to take action—like booking appointments, querying databases, or browsing the web—GPT-4 is still the gold standard. Its ability to output structured JSON is unmatched.
- Pros: highly reliable, massive developer ecosystem, widely supported.
- Cons: Can be expensive for high-volume tasks.
2. Claude 3.5 Sonnet (Anthropic)
The Human Touch.
Claude shines in conversation and nuance. It sounds less robotic and more empathetic, making it ideal for customer support agents where tone matters. Its large context window also makes it great for “reading” company documentation.
3. Gemini Pro 1.5 (Google)
The Multimodal Beast.
Gemini’s superpower is its native understanding of images and video. If you are building a tech support bot where users upload screenshots of errors, Gemini is the only real choice.
Comparison Table
| Model | Best Use Case | Cost |
|---|---|---|
| GPT-4 | Complex Logic / Tools | $$$ |
| Claude 3.5 | Support / Writing | $$ |
| Gemini | Multimodal / Speed | $ |
Verdict
For most OpenClaw users, we recommend starting with **GPT-4** for reliability, then optimizing with **Claude 3.5** if you need a cheaper, faster alternative for chat.