Skip to main content
U.S. flag

An official website of the United States government

xAPI Vocabulary Companion Specification Announced

March 02, 2016

The Experience API (xAPI), an open source API and technical specification developed under the ADL Initiative, provides a powerful way to store and retrieve data about learning activities of users or groups of users. The learning activity statements can present challenges when it comes to semantic interoperability though. When considering semantics, there are two fundamental challenges with natural language words:

  1. Two or more words can be used to represent a single concept (e.g., verbs such as "finished" and "completed").
  2. Two or more words that have the same spelling can represent different concepts (e.g., verbs such as passed (to physically move past) or passed (successfully pass an examination)).

xAPI terms are not natural language words, but approaches to handling natural language ambiguity inform approaches to handling xAPI ambiguity.  In order to address these challenges and others related to vocabulary discovery and reuse, a Companion Specification and Vocabulary Primer were recently published. These new resources were officially announced during xAPI Camp at AutoDesk in San Francisco, CA. This announcement comes nearly one year since the Vocabulary Considerations for xAPI white paper was published by ADL Initiative. Following the white paper, ADL Initiative facilitated a community-driven xAPI Vocabulary Working Group to investigate how to improve semantic interoperability for xAPI. These documents are applicable to anyone creating new vocabulary terms (Verbs or Activity Types) for xAPI. It is also applicable to any individuals or organizations developing applications for publishing, storing or retrieving vocabulary identifiers and definitions, or any other types of services that need to obtain the semantic meaning of xAPI vocabulary data.

ADL Initiative is requesting community feedback on these documents before applying vocabulary-specific revisions to the core xAPI Specification.