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

# API Introduction

> Introduction to the ABBYY Vantage REST APIs for intelligent document processing: Processing and Reporting APIs, OAuth 2.0 authentication, and base URLs.

The ABBYY Vantage platform provides two REST APIs for integrating intelligent document processing into your applications:

## Base URL

All API requests are made to the Vantage production server:

<CodeGroup>
  ```text US theme={null}
  https://vantage-us.abbyy.com
  ```

  ```text EU theme={null}
  https://vantage-eu.abbyy.com
  ```

  ```text AU theme={null}
  https://vantage-au.abbyy.com
  ```
</CodeGroup>

## Authentication

The Vantage API uses **OAuth 2.0** for authentication. Every request must include an access token in the Authorization header:

```bash theme={null}
Authorization: Bearer {your_access_token}
```

Vantage supports three authentication flows:

| Flow                                                                                                         | Best For                         |
| ------------------------------------------------------------------------------------------------------------ | -------------------------------- |
| [Resource Owner Password Credentials](/vantage/developer/authentication/resource-owner-password-credentials) | Server-to-server integrations    |
| [Authorization Code Flow](/vantage/developer/authentication/authorization-code-flow)                         | User-facing applications         |
| [Client Credentials](/vantage/developer/authentication/client-credentials)                                   | Machine-to-machine communication |

<Note>
  [Contact ABBYY](https://www.abbyy.com/company/contact-us/) to request a tenant in ABBYY Vantage. Once you have a tenant account, you can create user accounts and API clients for authentication.
</Note>

## Processing API

The Processing API (`/api/publicapi/v1/`) enables you to:

* **Create transactions** — Submit documents for processing with a specific skill
* **Manage files** — Upload, edit, and organize document images
* **Track status** — Monitor transaction progress and handle errors
* **Retrieve results** — Download extracted data in JSON or XML format
* **Manage catalogs** — Work with data catalogs and lookup tables

### Common Workflows

* **[Processing Documents with a Single API Call](/vantage/developer/processing-documents/processing-documents-single-api)** — Process documents with a single request that handles upload, processing, and result retrieval automatically.
* **[Processing Documents with Separate API Calls](/vantage/developer/processing-documents/processing-documents-with-separate-api-calls)** — Use separate API calls for fine-grained control over document upload, processing, and result retrieval.
* **[Integrating Manual Review](/vantage/developer/integrating-manual-review)** — Integrate manual review into your workflow for documents requiring human verification.

## Reporting API

The Reporting API (`/api/reporting/v2/`) provides access to:

* **Business metrics** — Transaction volumes, processing times, and throughput
* **Quality analytics** — Extraction accuracy and confidence scores
* **Field-level data** — Detailed extraction results for analysis

[Learn more about Reporting →](/vantage/developer/reporting/reporting-service)

## Output Formats

Vantage returns extracted data in structured formats:

* **[JSON Output](/vantage/developer/output/json/json-output)** — Hierarchical data with full extraction details and confidence scores
* **[XML Output](/vantage/developer/output/xml/xml-output)** — Structured markup for systems requiring XML integration

## Developer Resources

* **[Getting Started with the Vantage API](/vantage/developer/getting-started)** — Start here — make your first call, authenticate, and choose a processing scenario
* **[Postman Collection](/vantage/developer/postman-collection/overview)** — Ready-to-use API collection for testing and exploration

## Rate Limits & Best Practices

* **Batch operations** — Use batch endpoints when processing multiple records (up to 5,000 catalog records per request)
* **Polling** — When checking transaction status, use reasonable intervals (5-10 seconds)
* **Error handling** — Implement retry logic with exponential backoff for transient errors

## Next Steps

<Steps>
  <Step title="Set Up Authentication">
    [Configure OAuth 2.0](/vantage/developer/authentication/authentication) for your application
  </Step>

  <Step title="Process Your First Document">
    Follow the [processing guide](/vantage/developer/processing-documents/processing-documents) to submit a document
  </Step>

  <Step title="Explore the API">
    Browse the full [Processing API](/vantage/developer/processing-documents/processing-documents) and [Reporting API](/vantage/developer/reporting/reporting-service) references
  </Step>
</Steps>