User Guidance

To use data, you first need to understand its structure and meaning. OCDS data can contain fields from:

• OCDS, whose fields are described in its schema and in its Schema Reference.
• Extensions, whose fields are described in their schema and in their documentation.

To identify which extensions are used in OCDS data, you can either:

• Check for an extensions field at the package level. For data with extensions, this field contains an array of URLs to extension.json files. Each file contains a documentationUrl object with a URL to the extension's documentation. Open the URL to read its documentation (in many cases, the URL leads to this website). For example, the following data declares the Bid statistics and details extension:
  {"extensions": ["https://raw.githubusercontent.com/open-contracting-extensions/ocds_bid_extension/master/extension.json"]}
• Upload the data to the OCDS Data Review Tool, which lists the extensions used and links to their documentation.