[Route("api/[controller]")]
[ApiController]
public class KeepAliveController : ControllerBase
{
    [HttpPost]
    public IActionResult Post(KeepAliveContract keepAliveContract)
    {
        //
    }
}

public interface IKeepAliveService
{
    [Post("api/keepalive")]
    Task SendKeepAliveAsync(KeepAliveContract keepAliveContract);
}