how to install a single mod (not modpack)

[vista-narvas]

i want to use the https://www.curseforge.com/minecraft/mc-mods/libertys-villagers mod
but no matter what docker compose variables i try i always get 1 of 2 errors
im not sure what im doing wrong

Error 1. URL or slug identifier is required

A modpack page URL or slug identifier is required
[init] Running as uid=1000 gid=1000 with /data as 'drwxr-x--- 4 1000 1000 4096 Dec  6 20:57 /data'
[init] [ERROR] Failed to auto-install CurseForge modpack

Error 2. No mods found with slug

[init] Running as uid=1000 gid=1000 with /data as 'drwxr-x--- 4 1000 1000 4096 Dec  6 20:57 /data'
[mc-image-helper] 21:08:02.696 ERROR : 'install-curseforge' command failed. Version is 1.40.6
me.itzg.helpers.errors.GenericException: No mods found with slug=libertys-villagers
   at me.itzg.helpers.curseforge.CurseForgeApiClient.lambda$searchMod$2(CurseForgeApiClient.java:127)
   at reactor.core.publisher.MonoFlatMap$FlatMapMain.onNext(MonoFlatMap.java:132)
   at reactor.core.publisher.MonoFlatMap$FlatMapMain.secondComplete(MonoFlatMap.java:245)
   at reactor.core.publisher.MonoFlatMap$FlatMapInner.onNext(MonoFlatMap.java:305)
   at reactor.core.publisher.FluxContextWrite$ContextWriteSubscriber.onNext(FluxContextWrite.java:107)
   at reactor.core.publisher.FluxDoFinally$DoFinallySubscriber.onNext(FluxDoFinally.java:113)
   at reactor.core.publisher.MonoFlatMap$FlatMapMain.onNext(MonoFlatMap.java:158)
   at reactor.core.publisher.MonoPublishOn$PublishOnSubscriber.run(MonoPublishOn.java:181)
   at reactor.core.scheduler.SchedulerTask.call(SchedulerTask.java:68)
   at java.base/java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(Unknown Source)
   at java.base/java.util.concurrent.FutureTask.run(Unknown Source)
   at reactor.core.scheduler.SchedulerTask.call(SchedulerTask.java:28)
   at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
   at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
   at java.base/java.lang.Thread.run(Unknown Source)
   Suppressed: java.lang.Exception: #block terminated with an error
   	at reactor.core.publisher.Mono.block(Mono.java:1779)
   	at me.itzg.helpers.curseforge.CurseForgeInstaller.installByRetrievingModpackZip(CurseForgeInstaller.java:273)
   	at reactor.core.publisher.BlockingSingleSubscriber.blockingGet(BlockingSingleSubscriber.java:104)
   	at me.itzg.helpers.curseforge.CurseForgeInstaller.install(CurseForgeInstaller.java:183)
   	at me.itzg.helpers.curseforge.CurseForgeInstaller.lambda$install$3(CurseForgeInstaller.java:184)
   	at me.itzg.helpers.curseforge.CurseForgeInstaller.install(CurseForgeInstaller.java:229)
   	at me.itzg.helpers.curseforge.InstallCurseForgeCommand.call(InstallCurseForgeCommand.java:222)
   	at me.itzg.helpers.curseforge.InstallCurseForgeCommand.call(InstallCurseForgeCommand.java:30)
   	at picocli.CommandLine.access$1500(CommandLine.java:148)
   	at picocli.CommandLine$AbstractParseResultHandler.execute(CommandLine.java:2277)
   	at me.itzg.helpers.McImageHelper.main(McImageHelper.java:161)
[init] [ERROR] Failed to auto-install CurseForge modpack
   	at picocli.CommandLine.execute(CommandLine.java:2174)
   	at picocli.CommandLine$RunLast.execute(CommandLine.java:2421)
   	at picocli.CommandLine$RunLast.handle(CommandLine.java:2419)
   	at picocli.CommandLine$RunLast.handle(CommandLine.java:2457)
   	at picocli.CommandLine$RunLast.executeUserObjectOfLastSubcommandWithSameParent(CommandLine.java:2465)
   	at picocli.CommandLine.executeUserObject(CommandLine.java:2045)

my Docker compose

the commented out environment variables are things i tried

services:
  server:
    image: itzg/minecraft-server:latest
    # restart: unless-stopped # going to enable this when it works
    volumes:
      - data:/data
    ports:
      - "25565:25565"
    environment:
      TZ: 'Europe/Amsterdam'
      EULA: "TRUE"
      MAX_MEMORY: "4G"
      ENABLE_ROLLING_LOGS: true
      ALLOW_FLIGHT: true
      PLAYER_IDLE_TIMEOUT: 5
      TYPE: AUTO_CURSEFORGE
      CF_API_KEY: '$$2a$$10$$[CENSORED]'
      CURSEFORGE_FILES: "https://www.curseforge.com/minecraft/mc-mods/libertys-villagers"
      # CF_SLUG: "libertys-villagers"
      # CURSEFORGE_FILES: |
      #   https://www.curseforge.com/minecraft/mc-mods/libertys-villagers
      # CURSEFORGE_FILES: libertys-villagers
      # CF_SLUG: liberty-s-villagers
      # CF_PAGE_URL: https://www.curseforge.com/minecraft/modpacks/libertys-villagers
      # CF_PAGE_URL: https://www.curseforge.com/minecraft/mc-mods/libertys-villagers
      # CF_FORCE_INCLUDE_MODS: 700485
      # CF_FILES: libertys-villagers
      # CF_FILE_ID: 5447538
      # CF_MODS_FILE: /extras/mods.txt

volumes:
  data:

[itzg]

CURSEFORGE_FILES is the one to use

https://docker-minecraft-server.readthedocs.io/en/latest/mods-and-plugins/curseforge-files/

however you need to use a specific TYPE like "forge" and a VERSION that matches the mod.

[vista-narvas]

it works now 👍
Thank you for explaining it