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libretranslate service

libretranslate service runs a LibreTranslate instance on your machine, in a Docker container, so the SDK, the MCP server and the CLI have something to talk to.

It needs Docker. Without it, the command does not even show in libretranslate --help, and every subcommand first checks that Docker is installed and that its daemon answers, saying what to do when not.

npx libretranslate service up --languages en,pt,es   # create and start it, wait until it answers
npx libretranslate service status                    # container, image, URL, health (exit 3 when it does not answer)
npx libretranslate service logs --follow             # what it is doing (the first start downloads models)
npx libretranslate service down                      # stop it; --remove also deletes the container

Unlike the tool commands, it needs no saved configuration: it is how a local instance gets started in the first place.

up​

The first time, it pulls the image (with its progress), then creates the container:

  • named libretranslate, published on 127.0.0.1 only (port 5000, or --port);
  • with the language models in the libretranslate-models volume, so they are downloaded once;
  • with only the --languages given loaded, which makes it start much faster (default: every language);
  • from libretranslate/libretranslate:latest, or --image.

Then it waits for /health to answer (up to 15 minutes, --timeout <seconds>; --no-wait returns at once), and saves http://localhost:<port> as the CLI's instance when none is saved yet. When another instance is saved, it keeps it and prints the libretranslate mcp config --base-url … line to switch.

When the container already exists, up only starts it: --port, --languages and --image apply when it is created, so it says so. To change them, libretranslate service down --remove first.

The instance it runs issues no API keys, so nothing else is needed.

down​

Stops the container. --remove also deletes it; the models stay in the volume (docker volume rm libretranslate-models deletes them).

status and logs​

status prints the container's state, image, URL and whether /health answers, and exits with code 3 when it does not. logs prints the last 100 lines (--tail <n>), or keeps printing new ones with --follow (-f).