---
title: "Data Documentation"
canonical: https://www.quantconnect.com/docs/v2/lean-engine/contributions/datasets/data-documentation
markdown: https://www.quantconnect.com/docs/v2/lean-engine/contributions/datasets/data-documentation.md
language: python
source: https://github.com/QuantConnect/Documentation/tree/master/06%20LEAN%20Engine/02%20Contributions/01%20Datasets/06%20Data%20Documentation
modified: 2026-10-29
index: https://www.quantconnect.com/llms.txt
---

# Data Documentation

[Documentation](https://www.quantconnect.com/docs/v2.md) > [LEAN Engine](https://www.quantconnect.com/docs/v2/lean-engine.md) > Contributions > Datasets > Data Documentation

> Code examples are shown in Python. Append `?lang=csharp` to this URL for the C# version of this page.

## Introduction

This page explains how to provide documentation for your dataset so QuantConnect members can use it in their trading algorithms.

## Required Key Properties

You need to process the entire dataset to collect the following information:

| Property | Description |
| --- | --- |
| Start Date | Date and time of the first data point |
| Asset Coverage | Number of assets covered by the dataset |
| Data density | Dense for tick data. Regular or Sparse according to the frequency. |
| Resolution | Options: Tick, Second, Minute, Hourly, & Daily. |
| Timezone | Data timezone. This is a property of the data source. |
| Data process time | Time and days of the week to process the data. |
| Data process duration | Time to process the entire the dataset. |
| Update process duration | Time to update the dataset. |

## Provide Documentation

To provide documentation for your dataset, in the `Lean.DataSource.<vendorNameDatasetName> / listing-about.md` and `Lean.DataSource.<vendorNameDatasetName> / listing-documentation.md` files, fill in the missing content.

## Next Steps

After we review and accept your dataset contribution, we will create a page in our [Dataset Market](https://www.quantconnect.com/datasets). At that point, you will be able to write algorithms in QuantConnect Cloud using your dataset and you can contribute an example algorithm for the dataset listing. After your dataset listing is complete, we'll include your new dataset in our [downloading data tutorial](https://www.quantconnect.com/docs/v2/lean-cli/datasets/quantconnect/key-concepts.md#03-Using-the-CLI).