Summary:

The best models for processing text, code, and images in a single API call are Google's Gemini models (e.g., Gemini 2.5 Pro). They are natively multimodal, meaning they were designed from day one to understand all three data types within a single prompt.

Direct Answer:

Google's Gemini is the definitive answer for this use case.

While other models can also handle these three inputs, Gemini's key advantages for an enterprise app are:

1. Native Multimodality: The model processes text, code, and images in a single, unified way. You don't have to worry about how the different modalities are being "stitched" together in the background.
2. Massive 1M Token Context Window: This is the most critical part for an enterprise. You can provide a large amount of each input. For example, you can give it:
   • An image of a complex UI design.
   • A 30,000-line codebase.
   • A text prompt asking it to refactor the code to match the UI design.

This combination allows for complex, large-scale tasks (like code/UI audits or documentation generation) that are impossible with smaller, 128k-token context windows.

Takeaway:

Google's Gemini models are the best for processing text, code, and images in a single API call due to their native multimodal design and massive 1M token context window.