# Overview

The Rest API can be used with both the Open-Source platform and Opik Cloud. The main differences are related to the URL
to use and request headers used for authentication.

:::::tabs
:::tab{title="Open-Source"}
If you are using the Open-Source platform you can simply use the `http://localhost:5173/api/v1/<endpoint_path>`:

```bash
curl -X GET 'http://localhost:5173/api/v1/private/projects'
```
:::

::::tab{title="Opik Cloud"}
If you are using Opik Cloud or a on-premise installation of the Comet platform, you will need to specify the Opik
API Key and Opik Workspace in the header:

```bash
curl -X GET 'https://www.comet.com/opik/api/v1/private/projects' \
-H 'Accept: application/json' \
-H 'Comet-Workspace: <your-workspace-name>' \
-H 'authorization: <your-api-key>'
```

:::callout{intent="warning"}
Note that the authorization header value does not include the `Bearer ` prefix.
:::
::::
:::::

## Related pages

- [.NET](./net-index.md)
- [Administration](./administration-index.md)
- [AI Coding Assistants](./ai-coding-assistants-index.md)
- [Changelog](../changelog.md)
- [Configuration](./configuration-index.md)
- [Contributing](./contributing-index.md)
- [Development](./development-index.md)
- [Evaluation](./evaluation-index.md)
- [Getting Started](./getting-started-index.md)
- [Guardrails](./guardrails-index.md)

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