ModWatch
by Grashalm03
With ModWatch installed on a Paper or Spigot server, administrators can see which mods and resource packs each connected Fabric player is running.
What it does
A Fabric client mod sends its mod list and active resource packs to the server after a player joins. The ModWatch plugin for Bukkit, Spigot, Paper or Purpur receives that data and checks it against a blacklist of forbidden mod IDs, such as xray, Wurst and freecam, and kicks any player who runs one. A minimum mod version can also be enforced for chosen mods.
The protocol is a Join Handshake followed by Periodic Pings: the server requests data two seconds after a player joins, then sends a new random challenge every 30 seconds. A client that fails to reply, or replies with an invalid response, is kicked at once. Players cannot pass a check once and then disable the client, because the challenges keep arriving during the session.
The client mod runs on Fabric and Legacy Fabric, and the server plugin covers Bukkit, Spigot, Paper and Purpur. Either side can run it, and neither needs it, so the client mod is optional on the server and on players' machines alike. The license is All rights reserved, so the code is not open source. The latest file is 11.0.0 for 26.2, published 2026-08-01, and builds cover 1.0 – 26.2.
Key features
Mod list inspection
An administrator can see the full list of mods and active resource packs for a connected player with a single command.
Automated blacklist
Players running a forbidden mod ID are kicked immediately, and the kick message states that a blacklisted mod was found.
Periodic challenges
A hidden verification challenge is sent every 30 seconds, so a check cannot be passed once and then bypassed.
Global search
A scan command finds which online players use a specific mod, which helps when a single mod needs tracking across a server.
Minimum version enforcement
Server owners can require a minimum version of a chosen mod to keep the security standard consistent.
Gallery
Compatibility
Latest build for each game version and loader.
26.x4 of 4 versions with builds
1.21.x12 of 12 versions with builds
1.20.x7 of 7 versions with builds
1.19.x5 of 5 versions with builds
1.18.x3 of 3 versions with builds
1.17.x2 of 2 versions with builds
1.16.x6 of 6 versions with builds
1.15.x3 of 3 versions with builds
1.14.x5 of 5 versions with builds
1.13.x1 of 1 version with builds
Only full game releases are shown. This mod publishes no snapshot builds.
54 older game versions (1.0 – 1.13.1) not shown. All files on Modrinth
Use cases
Who it’s for: Server owners and administrators who run Minecraft servers with Fabric players and want to check that clients run no cheat or fair-play violating mods.
Questions
Does ModWatch need to be installed on the server and on clients?
Can a player get past a check after joining?
In the catalog
ModWatch is one of 8,499 Technology mods on ModsFinder, and one of 4,201 Technology mods for Fabric. 13,894 mods support Minecraft 26.2.
Similar mods
What the author says
The ultimate bridge between Server Administration and Player Integrity. ModWatch is a synchronization system designed to give server owners full visibility into the client-side environment of their players. By pairing a Bukkit/Spigot/Paper plugin with a lightweight Fabric client mod, you can ensure that your server…
Official listing
- Modrinth page
- modrinth.com/mod/modwatch
- Owner
- Grashalm03
- Published
- 2026-02-18
- Updated on Modrinth
- 2026-08-01
- Facts verified
- 2026-10-15