The Zotero Server API is split into two parts: a Read API, which allows you to retrieve item metadata from online Zotero libraries, either in the form of an Atom feed or as a formatted bibliography (rendered with citeproc-js), and a Write API, which allows you to modify online Zotero libraries.

Authorization for the Write API, or to read non-public libraries, relies on Zotero API keys, which can be generated either by users from their Zotero account settings or by developers via OAuth.

Known implementations of the Zotero Server API include:

• https://github.com/urschrei/pyzotero (Python)
• https://github.com/fcheslack/libZotero (PHP)
• https://github.com/clioweb/phpZotero (PHP, no longer maintained; formed the basis of libZotero)
• https://github.com/scholarpress/scholarpress-workshop

The API‌ forms a fundamental part of several projects, including:

• The online library view at zotero.org, which is built using the same read API‌
• Zotpress, a WordPress plugin for including citations to items in your Zotero library in blog posts. The plugin makes extensive use of the read API and implements both key-based and OAuth for access control.
• Biblio Bouts, an game where participants compete to collect high quality sources online. The game uses the API‌ to see what items participants have saved.
• phpZoteroWebDAV, a WebDAV implementation in PHP which allows users to sync their attachments to their own webservers, including an online library and attachment view building off the read API. (AGPL)
• Scanner for Zotero, Android app which saves items to Zotero libraries using the write API (Java, GPL-licensed)
• Zandy Android app using the read and write APIs to provide full access to Zotero libraries (Java, AGPL-licensed)
• ZotPad iPad/iPhone app using the read APIs to provide read access to Zotero libraries. Write access is planned. (Objective C, GPL-licensed)

Tutorial (under construction)