When using the New Relic REST API, you need to replace some ID placeholders (like
$COMPONENT_ID, etc.) with the ID for an app, transaction, or other component.
You can use the New Relic UI to get some of these IDs. You can also get a list of IDs using the REST API Explorer.
The UI includes the IDs of applications and some other components in a metadata panel.
Click the icon next to the application name to open the metadata panel.
Here are some examples: