The sqlagent application starts SQL Server Agent from the command prompt. Usually, SQL Server Agent should be run from SQL Server Service Manager or by using SQL-DMO methods in an application. Only run sqlagent from the command prompt when you are diagnosing SQL Server Agent, or when you are directed to by your primary support provider.
sqlagent -c [-v]
After displaying a copyright message, sqlagent displays output in the command-prompt window only when the -v switch is specified. To stop sqlagent, press CTRL+C at the command prompt. Do not close the command-prompt window before stopping sqlagent.