APIs, or Application Programming Interfaces, are the connectors that allow different software systems to communicate. They establish a standardized communication protocol for sending and receiving data, ensuring consistency across platforms. The OpenAPI Specification (OAS) is a popular format used to document these APIs in a machine-readable way (typically in JSON or YAML). Because it’s both comprehensive and machine-readable, OAS powers many automation scenarios in API testing, acting as a blueprint for test generation. 

Automated test generation has become a critical aspect of modern software development. As software systems grow in complexity, writing exhaustive tests manually becomes time-consuming, prone to errors, and can delay release cycles. Automated unit test generation helps developers create reliable, well-tested code efficiency, saving time and improving code quality.