Custom Data with APM APIs
There are a number of great APIs for different New Relic Products. For the APM Agent, there are two APIs that are commonly used and referenced; these are the Agent API and the REST API.
The Agent API
The Agent API is for controlling the agent and recording (or sending) data through the agent. There are several different types of custom data that can be sent to New Relic using the APM Agent API. Watch the APM Agent API tutorial series to learn how to add custom data to your New Relic APM account.
The REST API
This API is for getting data out of your New Relic account or changing settings. Create customized queries on metric names and metric data, including application server response times, page load times, and number of transactions and page loads. Also receive data about error rates and application server performance. Watch the REST API tutorial to learn how to access your New Relic account's performance data.