> ## Documentation Index
> Fetch the complete documentation index at: https://developers.gonitro.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Overview

> What Nitro Sign Enterprise Verified is, how its WebPortal API is structured, and how it authenticates.

## Welcome to Nitro Sign Enterprise Verified

**Nitro Sign Enterprise Verified (NSEV)** is Nitro's product for qualified, high-trust digital
signing - supporting a range of signing methods, including digital certificates and ID
verification, to meet strict regulatory requirements like eIDAS (AES/QES) and ZertES. It exposes
the **NSEV WebPortal API** (currently API version 4) for building secure document-signing
workflows: create a package, upload documents, add stakeholders and signing elements, then track
the package through to completion. If the package model is new to you, start with
[The package model](/docs/nsev/build/concepts/package-model).

NSEV is hosted by Nitro, with each customer served from their own tenant - so your API base URL
is tenant-specific. The product has its own API surface, authentication scheme, and
nomenclature - separate from the Nitro platform APIs documented under
[Nitro APIs](/docs/index).

This documentation describes the latest NSEV release (currently **v8.4**). Because releases roll
out to tenant deployments gradually, features introduced in a newer release are marked
*Available as of NSEV vX.Y* - see the [changelog](/docs/nsev/changelog) for what
changed in each release and for how to check which version your tenant runs.

## Get started

<Columns cols={2}>
  <Card title="Platform access" icon="key" href="/docs/nsev/getting-started/basic-setup">
    Get your credentials and find your tenant's base URL.
  </Card>

  <Card title="Make your first call" icon="rocket" href="/docs/nsev/getting-started/first-call">
    Verify your setup with an authenticated test request.
  </Card>

  <Card title="Send for signing" icon="signature" href="/docs/nsev/build/tutorials/send-for-signing">
    Walk through sending a document for signature end to end.
  </Card>

  <Card title="Best practices" icon="shield-check" href="/docs/nsev/build/guides/good-practices">
    Authentication, error handling, limits, pagination, and security.
  </Card>
</Columns>

## Base URL

The API base path is always `esig/webportalapi/v4`. Your host is tenant-specific - each NSEV
customer has a unique URL:

```
https://your-tenant.sign.gonitro.com/esig/webportalapi/v4
```

Your delivery team will confirm the exact host for your environment. See
[Platform Access](/docs/nsev/getting-started/basic-setup) for details.

## Authentication

The NSEV WebPortal API supports two authentication methods - HTTP Basic Auth and OAuth 2.0 Bearer
tokens - depending on how your organization has configured the platform. See
[Credentials & Authentication](/docs/nsev/authentication/credentials) for the
details of each method and when to use which.