Build an Outbound request Body in the HTTP Request Action, then map its Elements from values available before that request runs.

Configure the API's expected shape first, including objects and arrays. Map each generated value from an earlier Action, a Dynamic Input or another supported source.

Open the Payload, select HTTP Request and review Request Settings. Set the Content Type to the format required by the API and save the settings.

Use the Body section's New or Import controls to define the structure. Edit existing rows through the Body tree. Keep Element configuration inside this editor.

For JSON, XML and form URL encoded details, use the corresponding content-modelling guide.

Select HTTP Request to configure the generated request Body and its mappings.

Create any required Query before HTTP Request. In a Body Element mapping, set Value Source to Payload Data, select the Query Action and select the field.

For example, a checkout request can use an Opportunity Query for customer details and a child OpportunityLineItems collection for line items. A previously published Flow or child Payload output can also supply a value where its type matches.

Use Static Value for fixed API values. Use Dynamic Input for values supplied by Flow or the manual runner. Use Credential or Global Variable only where those sources are offered by the editor.

Set the Array's collection source, then map its child Elements from the current item. An Array sourced from OpportunityLineItems should read each item's product and price, rather than repeatedly reading one parent-level value.

Keep scalar values outside the Array when they belong to the whole request. Check top-level array requirements too; an API expecting an array should not receive an extra wrapper object.

Apply a Transformation when the source needs conversion to the API contract, such as a monetary amount represented in minor units. Confirm the API's actual requirement before choosing the calculation.

Test nulls, zero values and special characters. A visually correct tree can still build the wrong content if a source has no value or a conversion is incorrect.

Run a controlled test and open the Job. Select HTTP Request and inspect the recorded Body, including raw or tree views where available. Compare array counts and values with the earlier Query or other producer.

If a field is missing or repeated incorrectly, trace its source and current-item context. See Map data between Actions.