Skip to main content
The External Service task lets you connect your workflow to any REST API. You configure the endpoint, authentication, and request details—then map the response to use in later tasks.
For common services like Google Drive, Slack, or AWS S3, use the Integrations Task instead—it connects to 3,500+ services from the Integrations Marketplace and is simpler to set up.

​
Key Capabilities

Any REST API

Connect to any HTTP endpoint, public or private.

Flexible Authentication

Support for Bearer tokens, API keys, Basic auth, JWT, or no auth.

Full Control

Configure HTTP method, headers, and request body.

Structured Output

Returns request details and service response for downstream processing.

​
When to Use It

Use External Service when you need to call a custom API:
  • Connect to proprietary internal APIs
  • Access public APIs without built-in integrations
  • Send data to webhook endpoints
  • Fetch data from specialized services

​
The 5 Configuration Areas

To call an API, you’ll configure these five things:

​
Authentication Options

​
Output

The External Service task always returns two output variables:
To parse or extract specific fields from the Service Response, add an Opus Agent task after External Service to process and structure the data.

​
How to Add External Service

1

Drop it into your workflow

Drag an External Service task into your workflow where you need to call an API.
2

Enter the endpoint

Type the full API URL and select the HTTP method (GET, POST, etc.).
3

Set up authentication

Choose the authentication type and provide credentials if needed. For public APIs, select “None”.
4

Configure the request

Add any required headers and configure the request body.
5

Test it

Run a preview to verify the API call works and returns the expected response.
6

Parse the response

Add an Opus Agent task after External Service to extract specific fields from the Service Response.

​
Tips for Better Results

Before configuring External Service:
  • Test the API with a tool like Postman or curl
  • Verify your credentials work
  • Understand the response structure
APIs can fail for various reasons:
  • Check the response for success/failure status
  • Use a Decision Agent to handle error responses
  • Add fallback paths for when calls fail
Protect your API credentials:
  • Use organization-scoped credentials for shared APIs
  • Never hardcode secrets in request bodies
  • Use variables for sensitive values

Import Data

Pull data from services in the Integration Marketplace.

Export Data

Send data to services in the Integration Marketplace.

Opus Code

Write custom code for complex API logic.

Integrations

Explore all available integrations.