# Add a custom action to a step URL: https://docs.awellhealth.com/docs/design-care-flows/add-a-custom-action-to-a-step > For the complete documentation index, see [llms.txt](https://docs.awellhealth.com/llms.txt). Once an extension is installed, its actions appear in Studio alongside Awell's native ones. Install the extension before adding its action. See [Integrate with extensions](/docs/connect-systems/integrate-with-extensions). ## Add the action [#add-the-action] 1. Double-click the step that will hold it. 2. Click **Add action** and choose the custom action from the list. 3. Name the action so a colleague can tell what it does. 4. Configure its fields. Which fields exist depends on the extension. A custom action on a step, with the extension's own fields and tabs for what it sends, what it receives, and how errors are handled Each field takes either a fixed value or a data point, so the same action can be static for one care flow and patient-specific in another. ## Store the response when the care flow needs the result [#store-the-response-when-the-care-flow-needs-the-result] ### Without data points, only the side effect happens [#without-data-points-only-the-side-effect-happens] The action does its job and the care flow moves on. This is enough where only the side effect matters: a text message was sent, a record was created. ### With data points, the flow can react [#with-data-points-the-flow-can-react] The action's response is written into data points, so the rest of the care flow can use it. The flow can then branch on the result, put it in a message, or pass it to a later action. An appointment date the action fetches but doesn't store can't be used later in the care flow, and the flow can't react when the result is wrong. ## Next steps [#next-steps] * [Use variables in your actions](/docs/design-care-flows/use-variables-in-your-actions) to put stored values into messages. * [Build your own extension](/docs/extensions/get-started) if the action needed doesn't exist.