Qntrl’s Inbound REST Web Service allows you to create custom API endpoints that external users or systems can call to perform specific actions inside Qntrl. When a user triggers the API, Qntrl receives the request and processes it based on the configured logic in a Function script or Circuit.
One of the key features of Inbound REST is that customers can white-label their API URLs to reflect their own domain names, masking the Qntrl domain.
Key Highlights

If you want to customize your domain, use qntrls whitelabelling feature.
How It Works
External system sends API request.
Qntrl receives and authenticates the request.
Configured logic is executed via Function or Circuit.
Response is sent back, and related actions are triggered inside Qntrl.
Let’s walk through the steps to configure an Inbound REST request.
Create a Module
Each inbound REST API is grouped under a module, allowing you to organize related endpoints, such as those for jobs, layouts, or custom processes.
To create a module:
Navigate to
(
settings)
>> WEB SERVICES >> Inbound >> Select REST. Click New Inbound REST.
Fill in the following fields:
Name: Provide a logical name for the module (e.g., jobs, layouts). This helps group related APIs together.
Base URI: Define the base path for the APIs in this module (e.g., /jobs). This prefix will appear in all API endpoints created under this module.
Authentication Type: Qntrl uses the selected authentication type to validate incoming API requests. You can choose one of the following:
OAuth: Secure the API with OAuth scopes or global tokens for the organization.
Description: Add a brief description of the module or the purpose of the APIs it contains.
Click Create.

Once the module is created, a configuration window will open to define the API endpoint details.
In the open configuration window, you can enter the details directly if this is your first Inbound Resource. To add more later, click New Inbound Resource at the top-right corner of the page and fill in the following details to set up your API.
URL: Define the endpoint path (e.g., /create). This will be appended to the module’s base URI.
Method: Select the HTTP method — GET, POST, PUT, DELETE, OPTIONS, or PATCH.
Resource Type: Choose the type of handler to execute when this API is called.
Select an existing REST-type function or create a new one.
If creating a new function, write the script in the editor. The function will automatically be added to the Functions module with a generated name (you can rename it later).
Inside the function script, you can define how the incoming request should be handled and what response should be returned.
Function vs Circuit: How Resource Execution Works
Function Resource
When a function is selected as the resource:
The script can access and process request parameters, headers, body content, and file uploads.
You can define and return custom success or error responses with messages and HTTP status codes.
Files sent in the request can be handled as binary inputs.
This is ideal for use cases that require input validation, dynamic processing, or data manipulation.
Circuit Resource
When a circuit is selected as the resource:
The API triggers a predefined Qntrl Circuit.
The circuit receives the request parameters as input data, but cannot manipulate the request or perform validations.
File handling is not supported.
Response customization (e.g., HTTP status codes, custom messages) is not available.
You can define inputs and validations for requests to this endpoint.

Save and Publish
Once the API endpoint and request components are configured,
Click Save to create the endpoint.
It will appear on the left side under Resources, where you can edit or delete it anytime.
The endpoint is now ready to receive API requests and run the linked function or circuit.

If any validation fails for request params, headers, or body, Qntrl will reject the request.
Warnings and errors can be handled and returned only when using Function as the resource.
Circuits provide only basic automation triggers without detailed input/output control.
How to Send a REST API Request to Qntrl
To send a REST API request to Qntrl, use the following format:
Method: Any HTTP method (e.g., GET, POST)
URL: https://core.qntrl.com/webservice/<org_id>/<base_URI>/<source_endpoint>
Authentication (must be added in the request header):
- OAuth Token
Header Format: Authorization: Zoho-oauthtoken <access_token>
Required OAuth Scopes:
ws_restinbound.UPDATE
ws_soapinbound.UPDATE
API Key
Header Format: Authorization: Bearer <api_key>
Other Actions
Edit or Delete a Module
Navigate to
(settings) >> WEB SERVICES >> Inbound >> Select REST.
Hover over the action menu (three dots) next to the module name.
Select:
Activate or Deactivate a Module
Navigate to
(settings) >> WEB SERVICES >> Inbound >> Select REST.
In the Status section of the category, use the toggle switch to activate or deactivate a module.
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