Using OpenRouter to switch between many LLMs

Why use more than one LLM?

One model might be a strong research assistant, such as Claude-4 Opus. Another might be a fast sparring partner for brainstorming, such as a fine-tuned Llama 3 variant. A third might describe images, such as LLaVA or GPT-4 Vision through OpenRouter.

OpenRouter.ai lets you switch between these models in one place. For a hard coding problem, pick a model known for logic. For a romantic sonnet, pick one with a more flowery style. OpenRouter also tracks usage and potential costs, which helps when you compare what different models charge to summarize a long document.

What OpenRouter.ai provides

• Access to a large range of models from providers such as OpenAI, Anthropic, Google, Cohere and Mistral, plus many open-source options, through one API. You do not need a separate API key for each.
• A consistent API format. You write the integration once and change the model identifier to use another model.
• Clear information about model capabilities, context window sizes and pricing before you make a call.
• Switching takes one edit. If a model does not suit a task, or a newer one appears, change the model identifier.

Switching models lets you send each sub-task to the model that suits it. You can also send the same prompt to two models and compare the answers for quality and tone.

Choosing a model for each task

Favorites form quickly for specific tasks. One model may feel more empathetic for creative writing. Another may be more accurate for factual questions or code.

Gemini Pro through OpenRouter is my choice for summarizing reports. For an unusual creative story, I switch to MythoMax.

OpenRouter is the gateway. The models you access may have their own memory features.

To compare two models, send the same prompt to both through OpenRouter and see which answer fits the task better.