What is the context length of Horizon Alpha?

Horizon Alpha has a 256,000 token context window.

What inputs and outputs does Horizon Alpha support?

Horizon Alpha accepts images and text as input and returns text.

When was Horizon Alpha released?

Horizon Alpha was released on July 30, 2025.

All prompts and completions for this model are logged by the provider and may be used to improve the model and other products and services.

Horizon Alpha

openrouter/horizon-alpha

This was a cloaked model provided to the community to gather feedback. It has been deprecated - see Horizon Beta.

Note: It’s free to use during this testing period, and prompts and completions are logged by the model creator for feedback and training.

Modalities

Context

256K

Released

Jul 30, 2025

Not currently available through EU in-region routing. In-region routing docs

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Horizon Alpha

Activity

Frequently asked questions

What is Horizon Alpha?

What is the context length of Horizon Alpha?

What inputs and outputs does Horizon Alpha support?

When was Horizon Alpha released?

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