To get a list of types, use @param Type:

To get a list of states, use @param State:

To get a list of fields, use @param Field:<field type>:

For example, to get a list of relationship fields type:

This prevents introducing typographical errors into trigger parameters and having to look up type, state, and field names. The syntax for all field types is the field type name (all lowercase and no spaces), for example, Long Text is “longtext”.