Siren

Siren clearly defines entities with properties, sub-entities, actions, and links, as shown in the example order with embedded items and customer info, making API responses self-descriptive and easy to parse.

Includes actions with methods, fields, and hrefs, allowing clients to discover available behaviors, like the 'add-item' action in the example that specifies POST method and form fields for state transitions.

Facilitates non-CRUD designs by letting root entities manage sub-entity changes, enabling APIs to expose complex workflows, as highlighted in the 'Usage Considerations' section.

Siren is media-type agnostic, starting with JSON but designed for other implementations like XML, offering flexibility for future adaptations, per the introduction.