YAML Schema
To create a YAML Schema file of your entity, choose the menu Tools > Forward Engineering > YAML Schema:

then select the directory path and file name.
The YAMLSchema for the entity can also be viewed in the left-hand pane of the JSON Preview tab:

Several important options are available:
1) YAML Schema compliance:
- standard: only YAML Schema keywords and data types are used -- this output should pass validation with standard validators
- full: custom keywords are also listed for a full view of the schema, but only standard YAML data types are used -- this output should pass validation as long as additionalProperties are set to true
- extended: data types are specific to the target of the model, plus internal properties and keywords are also listed.
Important
In extended compliance, it is normal that the exported YAML Schema does not pass the test of validators. This is because data types used for a given target may be non-YAML data types. For example ObjectId for MongoDB, or UUID in Cassandra, etc...
2) Definitions:
- referenced: definitions are referenced as described in the model, using $ref syntax
- resolved:: definitions are resolved to list the content of the reference.
- internal: references to external and model definitions are converted into internal definitions