__EMPTY__ sentinel value.
Simple Use Case
Problem: Sometimes workflows have optional form fields that should be skipped when no data is provided. Solution: Use__EMPTY__ to skip typing while maintaining workflow structure.
Example
Automatic __EMPTY__ for Missing Nested Fields
When using structured inputs with nested access, missing fields automatically become __EMPTY__:
__EMPTY__ values.
Type errors are different: If you try to access a nested property on a value that isn’t an object or array (e.g.,
{patient.name.first} when patient.name is a string), the run fails immediately with a clear error. Only truly missing fields become __EMPTY__.When to Use
- Optional form fields that might not always be filled
- Progressive workflows where some data is provided later
- A/B testing different workflow variants
- Graceful degradation when inputs are missing
- Nested optional fields in structured input objects