Empty Values

When developers want to skip certain form fields in workflows, Cyberdesk provides the __EMPTY__ sentinel value. If you want to actively clear an already-filled field instead, use __CLEAR__. Cyberdesk also treats optional empty strings and null values as “not provided” when building run inputs, so they are normalized to __EMPTY__ before execution.

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

# User provides username but no email
input_values = {"username": "john_doe", "email": "__EMPTY__"}

# Agent behavior:
type_text("john_doe")  # Types the username
type_text("__EMPTY__")  # Skips typing (no email provided)

Automatic `EMPTY` for Missing Nested Fields

When using structured inputs with nested access, missing fields automatically become __EMPTY__:

# Prompt uses: {patient.middle_name}
# Input only has first and last name:
input_values = {
    "patient": {
        "first_name": "John",
        "last_name": "Doe"
        # middle_name is not provided
    }
}

# Result: {patient.middle_name} → __EMPTY__

This allows workflows to gracefully handle optional nested fields without requiring explicit __EMPTY__ values.

Nested Access on `EMPTY` Values

If a root variable is __EMPTY__ and you try to access a nested property on it, the result is also __EMPTY__:

# Prompt uses: {extra_info.notes}
# User provides nothing for extra_info (auto-converted to __EMPTY__)
input_values = {"extra_info": "__EMPTY__"}

# Result: {extra_info.notes} → __EMPTY__

This allows workflows to gracefully skip entire optional sections without failing.

Type errors are different: If you try to access a nested property on a value that is a concrete type like a string or number (e.g., {patient.name.first} when patient.name is "John Doe"), the run fails immediately with a clear error. Only missing fields and __EMPTY__ values become __EMPTY__.

Input Schema Validation

When a workflow has an input schema, __EMPTY__ is treated as “not provided” for validation.

Object fields set to __EMPTY__ are ignored during schema validation.
Array entries set to __EMPTY__ are removed before validation.
This applies to auto-generated __EMPTY__ values too, including optional inputs left blank as empty strings or null.

This lets optional fields stay blank without failing validation, while required fields still need a real value unless your schema allows them to be omitted.

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

Best Practice

# ✅ Good: Simple optional step
type_text("__EMPTY__", conditional="input_values['optional_field'] == '__EMPTY__'")

# ❌ Avoid: Complex logic - split workflows instead

This is a simple convenience feature for handling occasional missing data - not for complex workflow logic. If you need to blank out an existing value instead of skipping, see Clear Values.

Getting started

SDK Guides

Cyberdriver

Workflow Prompting

Webhooks

Concepts

Additional Details

Simple Use Case

Example

Automatic `EMPTY` for Missing Nested Fields

Nested Access on `EMPTY` Values

Input Schema Validation

When to Use

Best Practice

​Simple Use Case

​Example

​Automatic __EMPTY__ for Missing Nested Fields

​Nested Access on __EMPTY__ Values

​Input Schema Validation

​When to Use

​Best Practice

Simple Use Case

Example

Automatic `EMPTY` for Missing Nested Fields

Nested Access on `EMPTY` Values

Input Schema Validation

When to Use

Best Practice