# API Interface

## Authentication

Cloud uses API keys for authentication. An API key is a token provided by the client when making API calls. The key should be sent as a request header named X-API-Key:

📚 How to get my API key? [Here](https://www.ycloud.com/console/#/app/developers/apikey?)\
Get your API key

📙 If you prefer SDKs, we offer multiple languages. Download our [SDKs](https://github.com/ycloud-developers) here.

## Testing the API

This is the SMS API documentation <https://ycloud.readme.io/reference/sms-send>\
You can enter the API key and parameters to test the message

<figure><img src="/files/NTBbZ5Gb1J30yWv9w3je" alt=""><figcaption></figcaption></figure>

## Response

Open the response to view the full parameters.

<figure><img src="/files/JfjhE2SE4e7sMOmbxrRI" alt=""><figcaption></figcaption></figure>

## Error Codes

[If you receive any error codes, you can check their meanings here](https://ycloud.readme.io/reference/errors#error-codes)


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# Agent Instructions: Querying This Documentation

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

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://helpdocs.ycloud.com/help-center/integrations/channels/global-sms/sms-features/api-interface.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
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.