The "AG Server Stats" plugin you described appears to be a Minecraft plugin that shows real-time server statistics in game via placeholders. It supports specifying multiple IPs in config.yml to query server statuses that auto-update every minute, and outputs many placeholders like %agserverstats_status%. Here is an overview and how such a plugin typically works and can be simplified:

Core Features

Has a config.yml where server IPs can be listed infinitely to monitor.
Uses placeholders (e.g., %agserverstats_status%) that players or other plugins can use to display real-time server statuses inside the game.
Automatically reloads or updates the server status data every 1 minute.
Shows details such as server online/offline status, player counts, etc.
To support placeholders like

%agserverstats_<servername>_status%

with dynamic server names, integrated with PlaceholderAPI and usable in TAB plugin (which supports PlaceholderAPI), the plugin needs:

How to implement dynamic placeholders for each server In config.yml, each server entry should have a unique name identifier, e.g.:

servers:
server1:
ip: mc.hypixel.com
port: 25565
server2:
ip: play.crazymc.fun
port: 25571

1. %agserverstats_server1_status%
2. %agserverstats_server2_status%
Installation

Download AGSeverstats.jar
Place it into your server’s /plugins folder
Restart or reload your server
Edit the config.yml as needed
Use /ags reload to apply changes
Commands:

/ags or agserverstats reload
/ags or agserverstats changename <servername> <newname>
/ags or agserverstats changeip <servername> <newip>
/ags or agserverstats status <servername>