Common Workflow Language Specifications, v1.0.2 §
The CWL specifications are divided up into several documents.
The User Guide provides a gentle introduction to writing CWL command line tools and workflows.
The Command Line Tool Description Specification specifies the document schema and execution semantics for wrapping and executing command line tools.
The Workflow Description Specification specifies the document schema and execution semantics for composing workflows from components such as command line tools and other workflows.
The Semantic Annotations for Linked Avro Data (SALAD) Specification specifies the preprocessing steps that must be applied when loading CWL documents and the schema language used to write the above specifications.