Where is the Body Builder (beta) documentation?

The Body Builder (beta) documentation on OpenRouter includes the Body Builder guide. The quickstart covers API keys and your first request, and the API reference lists every parameter.

How much does Body Builder (beta) cost?

Body Builder (beta) has no fixed price of its own. Each request is billed at the price of the model that serves it, so your cost depends on which model the request is routed to.

What is the context length of Body Builder (beta)?

Body Builder (beta) can route to models with context windows of up to 128,000 tokens. The context length available to a request is that of the model that serves it.

When was Body Builder (beta) released?

Body Builder (beta) was released on December 5, 2025.

Body Builder (beta)

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Transform your natural language requests into structured OpenRouter API request objects. Describe what you want to accomplish with AI models, and Body Builder will construct the appropriate API calls. Example: "count to 10 using gemini and opus."

This is useful for creating multi-model requests, custom model routers, or programmatic generation of API calls from human descriptions.

BETA NOTICE: Body Builder is in beta, and currently free. Pricing and functionality may change in the future.

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

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Body Builder (beta)

API

Documentation

Frequently asked questions

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Frequently asked questions

What is Body Builder (beta)?

Where is the Body Builder (beta) documentation?

How much does Body Builder (beta) cost?

What is the context length of Body Builder (beta)?

When was Body Builder (beta) released?

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