> For the complete documentation index, see [llms.txt](https://docs.xaman.dev/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.xaman.dev/concepts/special-transaction-types/signin.md).

# SignIn

{% hint style="success" %}
Note that the `SignIn` transaction type is already embedded in the Xaman SDK and OAuth flows. You only need the `SignIn` transaction type if you are manually building your own integrations (e.g. API integrations:[Backend (SDK / API)](/environments/backend-sdk-api.md))
{% endhint %}

**The SignIn transaction type is Xaman specific, signature only, can never be submitted.** When sending a JSON transaction payload, you can use all XRPL transaction types, including a Xumm-specific "pseudo transaction type": `SignIn`.

The payload for a SignIn transaction can look like this:

```json
{
  "txjson": {
    "TransactionType": "SignIn"
  }
}
```

\
After the user signs your SignIn request, the server-to-server call (to your configured Webhook location) will receive the signed transaction containing the signed transaction HEX blob.

You can verify the signature using the `verify-xrpl-signature` package:\
<https://github.com/XRPL-Labs/verify-xrpl-signature>

**Note**: The `SignIn` transaction type is particularly useful when you want to authenticate a user without performing any transaction on the XRPL.


---

# 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 dynamically by asking a question.

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

```
GET https://docs.xaman.dev/concepts/special-transaction-types/signin.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

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.