For API Monitoring, formerly known as Runscope, only the latest version of the Radar agent is supported.
How to upgrade to the latest version?
1. Download the latest agent for the applicable platform, see section "Downloading and Running the Agent" in this article
2. Extract the runscope-radar binary from the zip file.
3. Stop the currently running agent.
4. Replace the current runscope-radar by the latest downloaded version and give it execute permissions.
5. Restart the agent.
To determine the version of the current or upgraded version, run
$ ./runscope-radar --version