> ## Documentation Index
> Fetch the complete documentation index at: https://doc.onetoken.one/llms.txt
> Use this file to discover all available pages before exploring further.

# Configure OneToken in DeepSeek Harness

[DeepSeek Harness](https://www.deepseek.com/harness/) is an AI coding tool from DeepSeek. You can add OneToken as a custom model provider and use OneToken-supported models in Harness.

## Prerequisites

Before you begin, make sure you have:

* Installed Node.js and npm.
* Created an API key in the [OneToken console](https://onetoken.one/console/token).
* Copied the model ID you want to use from the [OneToken model marketplace](https://onetoken.one/pricing).

## Install and start DeepSeek Harness

Run the following command in your terminal:

```bash theme={null}
npx @deepseek-ai/dsh web
```

After the command starts, open DeepSeek Harness in your browser.

## Configure OneToken

### 1. Open Settings

Click **Settings** in the lower-left corner.

<img src="https://mintcdn.com/onetoken-9a3c590a/U-i0KEuXhPAAgbYS/images/DeepseekHarness/en/1.png?fit=max&auto=format&n=U-i0KEuXhPAAgbYS&q=85&s=1c3c9f616304deb244d2283d2b3460d7" alt="Settings entry on the DeepSeek Harness home page" width="2392" height="1574" data-path="images/DeepseekHarness/en/1.png" />

### 2. Add a custom provider

Open **Models**, then click **Add a custom provider**.

<img src="https://mintcdn.com/onetoken-9a3c590a/U-i0KEuXhPAAgbYS/images/DeepseekHarness/en/2.png?fit=max&auto=format&n=U-i0KEuXhPAAgbYS&q=85&s=3b4a4655898c3020f1e932aae2467ee5" alt="Add a custom provider button in DeepSeek Harness model settings" width="1776" height="1072" data-path="images/DeepseekHarness/en/2.png" />

### 3. Enter the provider details

Complete the provider configuration with these values:

* **Provider ID**: Enter `onetoken`. The value must begin with a lowercase letter.
* **Display name**: Enter `OneToken`, or choose another recognizable name.
* **Base URL**: Enter `https://onetoken.one/v1`.
* **API protocol**: Select `openai-completions`.
* **API key**: Paste your OneToken API key.

Add the models you want to use under **Models**:

* In the first field, enter the model ID copied from the OneToken model marketplace, such as `deepseek-v4-flash-0731`.
* In the second field, enter the name that Harness should display, such as `DeepSeek-V4-Flash`.
* To configure more models, click **Add model** and enter each additional model.

Review the configuration, then click **Apply**.

<img src="https://mintcdn.com/onetoken-9a3c590a/U-i0KEuXhPAAgbYS/images/DeepseekHarness/en/3.png?fit=max&auto=format&n=U-i0KEuXhPAAgbYS&q=85&s=73df1fec96d98a32b76e2407864ee891" alt="OneToken custom provider configuration in DeepSeek Harness" width="1660" height="1546" data-path="images/DeepseekHarness/en/3.png" />

## Select a workspace and model

Return to the home page and select an existing workspace from the workspace menu. To use a different local directory, click **Add workspace**.

<img src="https://mintcdn.com/onetoken-9a3c590a/U-i0KEuXhPAAgbYS/images/DeepseekHarness/en/4.png?fit=max&auto=format&n=U-i0KEuXhPAAgbYS&q=85&s=d7e3a4c876c0ced8065431bf6bfdeed0" alt="Selecting a workspace in DeepSeek Harness" width="1822" height="922" data-path="images/DeepseekHarness/en/4.png" />

Open the model menu in the lower-right corner of the prompt box. Select the model you configured and the effort level you want. Enter a task and send it to start using the model.

<img src="https://mintcdn.com/onetoken-9a3c590a/U-i0KEuXhPAAgbYS/images/DeepseekHarness/en/5.png?fit=max&auto=format&n=U-i0KEuXhPAAgbYS&q=85&s=326f58545cd03af115af58c856206949" alt="Selecting a OneToken model in DeepSeek Harness" width="1688" height="688" data-path="images/DeepseekHarness/en/5.png" />

<Note>
  Never expose your API key in screenshots, logs, or public files.
</Note>


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