> For the complete documentation index, see [llms.txt](https://omnitool-ai.gitbook.io/omnitool/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://omnitool-ai.gitbook.io/omnitool/tutorial/blocks/openrouter.md).

# OpenRouter

The OpenRouter Block is a unified API that specializes in providing access to a diverse range of [supported Large Language Models (LLMs)](https://openrouter.ai/docs#models). 

## Prerequisites

Before you begin, ensure you have:

* **OpenRouter Account:** Register or sign in at [OpenRouter's website](https://openrouter.ai/).
* **API Key:** Obtain your [OpenRouter Key](https://openrouter.ai/keys).
* **Credits:** Ensure you have enough API credits. (You have a small usage allowance (< $1) before you need to pay).

## Setup

### Adding API Key

1. Access the API Key Manager in Omnitool's left panel.
2. Input your OpenRouter API key.

## Using the OpenRouter Block

1. Navigate to the "Add Block" collection within Omnitool.
2. Search for the `openrouter` namespace to locate its LLM block.
3. There are two distinct LLM blocks provided. One of these is the vision transformer LLM model block, which is designed to process image input.

<figure><img src="/files/Py3vEPCceF6VWiGe1EhK" alt=""><figcaption></figcaption></figure>

## Additional Resources

For developers and users seeking more advanced configurations and troubleshooting resources for these blocks, refer to the OpenAPI and block specifications on the <https://github.com/omnitool-ai/omni-core-blocks/tree/main/server/apis/openrouter>.

***

For additional details on the OpenRouter API, refer to the [OpenRouter website](https://openrouter.ai/docs#quick-start).<br>


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