OpenRouter: One Account for Hundreds of AI Models
OpenRouter lets you reach models from many AI companies through a single API (a programming interface that lets your code talk to a service), according to Simon Willison. It "handles fallbacks automatically and picks the most cost-effective option for each request."
That convenience has a catch, flagged by developer Mohamed Moustafa. One model is often served by several backend providers running different software, so identical requests can behave differently. Some providers lack vision support even when the model has it.
To start, create an account at openrouter.ai. Call its /endpoints method with a model ID to see which providers serve that model, then lock requests to the one you want with the provider.only option.
Worth knowing: Without pinning a provider, the same model can give different results between requests, which matters if you are testing or comparing models.
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