UiPath Documentation
maestro
latest
false

Maestro user guide

API Workflow

Invokes a UiPath Studio Web API workflow and returns its output.

When to use API Workflow vs HTTP Request

Use the API Workflow node when the logic you need to call is built in Studio Web and published as an API workflow — for example, structured data processing or multi-step integrations authored by your team. Use the HTTP Request node when you are calling any external Representational State Transfer (REST) endpoint outside the UiPath Platform.

Configuration

FieldRequiredDescription
API workflowYesThe Studio Web API workflow to invoke. Select from the list of published API workflows in your organization.
InputNoKey-value pairs mapped to the API workflow's input parameters. Supports variable references.
TimeoutNoMaximum time to wait for the workflow to complete.

Output variables

VariableDescription
outputThe response returned by the API workflow, according to its output schema.
errorError details when the call fails. Use it with error handling to branch on failures.

Examples

Reference the API workflow's output downstream with an expression:

$vars.apiWorkflow1.output
$vars.apiWorkflow1.output

To use a single field from the output, append the field name defined by the API workflow's output schema — for example, $vars.apiWorkflow1.output.<field>.

Common issues

IssueResolution
API workflow not listed in the dropdownEnsure the workflow is published in Studio Web and you have permission to invoke it.
Timeout errorIncrease the Timeout value or optimize the Studio Web workflow for faster execution.
Input type mismatchCheck that the variable types you are passing match the API workflow's declared input parameter types.

Was this page helpful?

Connect

Need help? Support

Want to learn? UiPath Academy

Have questions? UiPath Forum

Stay updated