The New Relic Node.js agent API allows you to extend the agent's standard functionality. You can use this API to:
Customize your app name
Create custom transaction parameters
Report custom errors and metrics
You can also use the API for custom instrumentation. For supported frameworks, the agent instruments most activity automatically. Custom instrumentation lets you extend that monitoring to frameworks without default instrumentation.
The Node.js agent API documentation on GitHub has more detail and practical tutorials.
You can also adjust the Node.js agent's default behavior with configuration settings.
To see all available New Relic APIs, see Intro to APIs.