How to register a service that is managed by homebrew?

[Lyken17]

For example, the brew service for shadowsocks-libev is

~/Library/LaunchAgents/homebrew.mxcl.shadowsocks-libev.plist

 <?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
 <plist version="1.0">
   <dict>
     <key>Label</key>
     <string>homebrew.mxcl.shadowsocks-libev</string>
     <key>ProgramArguments</key>
     <array>
       <string>/usr/local/opt/shadowsocks-libev/bin/ss-local</string>
       <string>-c</string>
       <string>/usr/local/etc/shadowsocks-libev-server.json</string>
       <string>-u</string>
     </array>
     <key>RunAtLoad</key>
     <true/>
     <key>KeepAlive</key>
     <true/>
   </dict>
 </plist>

I want to make a second service (with different configuration) and register to homebrew service. I modified the content and then move to

~/Library/LaunchAgents/homebrew.mxcl.shadowsocks-libev-2.plist

 ......
     <string>homebrew.mxcl.shadowsocks-libev-2</string>
     <key>ProgramArguments</key>
     <array>
       <string>/usr/local/opt/shadowsocks-libev/bin/ss-local</string>
       <string>-c</string>
       <string>/usr/local/etc/shadowsocks-libev-server-2.json</string>
 ......

But it does not show in brew service list neither can be run as brew register run

ligeng@Lgs-Mac-mini➜  LaunchAgents brew services list
Name              Status  User   Plist
shadowsocks-libev started ligeng /Users/ligeng/Library/LaunchAgents/homebrew.mxcl.shadowsocks-libev.plist

ligeng@Lgs-Mac-mini➜  LaunchAgents brew services run shadowsocks-libev-2
Error: No available formula with the name "shadowsocks-libev-2"

How can I register it to brew service?

[MikeMcQuaid]

How can I register it to brew service?

It needs to be part of a formula.

Instead, just use launchctl directly.