> For the complete documentation index, see [llms.txt](https://developer.singular.live/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.singular.live/data-stream-api/how-to-guides/send-data-to-an-app-using-the-data-stream-api.md).

# Send data to an app using the data stream API

In this how-to guide, you'll learn how to send data to an app using the data stream API.

### Requirements

1. You have [created a data stream](/data-stream-api/how-to-guides/create-a-data-stream.md)
2. You have [linked the data stream to a composition](/data-stream-api/how-to-guides/link-a-data-stream-to-a-composition.md)

This guide is language and platform agnostic. Thus, you can follow along using cURL or whatever language you use to make API requests as well as on Postman or the API platform of your choice. To try it out on Postman, visit the [Singular Postman collection](https://documenter.getpostman.com/view/2177855/2s83zcTSu6).

### How to send data to an app using the data stream API

1. Prepare a `PUT` request to send to `https://datastream.singular.live/datastreams/:datastreamPrivateToken`, which is the endpoint for the [Singular data stream API](/data-stream-api/api-reference.md). 
2. Replace `:datastreamPrivateToken` with the actual private token. (This can be found on the [data stream manager](https://app.singular.live/datastreammanager), located on the user menu on the Singular Dashboard.) 
3. Add a request body that matches the format of, and updates, the [payload of the sub-composition](/rest-api/how-to-guides/get-a-compositions-sub-composition-ids-and-names-and-their-payload-structures.md) that is connected to the data stream in the overlay's composition.
4. With the composition editor in Composer open, send the request and watch the data update.


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://developer.singular.live/data-stream-api/how-to-guides/send-data-to-an-app-using-the-data-stream-api.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.