AssertionFailureOnField is a union datatype based on the different ways in which an assertion may fail. You'd use the parameters of FieldUnexpectedlyPresent, or FieldHadUnexpectedValue, or FieldHadConflictingAssertions, or AssertionOnFieldWasOrphaned datatype. Below are the tables for each datatype:

Table: FieldUnexpectedlyPresent

ParameterTypeRequiredDefaultStabilityAvailabilityDescription
Some input parameters may be required, as indicated in the Required column. For return values, this indicates that you are assured a value if the field is requested for the results. 
Table last updated: Oct 14, 2026 
actualValueStringyes Long-Term The value that the field contained.
fieldNameStringyes Long-Term The field being asserted on.

Table: FieldHadUnexpectedValue

ParameterTypeRequiredDefaultStabilityAvailabilityDescription
Some input parameters may be required, as indicated in the Required column. For return values, this indicates that you are assured a value if the field is requested for the results. 
Table last updated: Oct 14, 2026 
actualValueString  Long-Term The actual value of the field. Note that this is null in the case where the field wasn't present.
expectedValueStringyes Long-Term The value that was asserted to be contained in the field.
fieldNameStringyes Long-Term The field being asserted on.

Table: FieldHadConflictingAssertions

ParameterTypeRequiredDefaultStabilityAvailabilityDescription
Some input parameters may be required, as indicated in the Required column. For return values, this indicates that you are assured a value if the field is requested for the results. 
Table last updated: Oct 14, 2026 
fieldNameStringyes Long-Term The field being asserted on.

Table: AssertionOnFieldWasOrphaned

ParameterTypeRequiredDefaultStabilityAvailabilityDescription
Some input parameters may be required, as indicated in the Required column. For return values, this indicates that you are assured a value if the field is requested for the results. 
Table last updated: Oct 14, 2026 
fieldNameStringyes Long-Term The name of the field which is being asserted.