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name: opennmt-py description: "Routes OpenNMT-py workflows for data preparation, training, inference, server deployment, and checkpoint/model conversion." disable-model-invocation: true metadata: disco-role: operating license: MIT

OpenNMT-py

Use this skill for OpenNMT-py tasks that involve corpus preparation, vocabulary building, training, translation, REST serving, checkpoint maintenance, or model conversion.

Install

For a local checkout, prefer an editable install:

python -m pip install -e .

For a published install:

python -m pip install "OpenNMT-py==3.5.1"

Core runtime facts:

• Python 3.9+
• PyTorch 2.1 to <2.3
• The package expects torch, ctranslate2, pyonmttok, and pyyaml to be present.
• Optional workflows add sentencepiece, safetensors, pandas, gradio, and bitsandbytes.

Minimal smoke check:

python -c "import onmt, torch; print('onmt_import=ok'); print(torch.__version__, torch.cuda.is_available())"

If you need CUDA paths, read references/compatibility.md and run scripts/check_cuda.py.

Route map

• sub-skills/data-preparation/ — build vocabularies, validate corpus YAML, apply transforms, handle source features, and debug data layout issues.
• sub-skills/training/ — train seq2seq or language models, inspect model configs, handle multi-GPU, embeddings, alignment, LoRA, and checkpointing.
• sub-skills/inference/ — translate, score, align, run the REST server, and use CTranslate2 or LLM-style inference configs.
• sub-skills/conversion/ — convert external checkpoints, upgrade old checkpoints, extract or merge weights, and release models.

Start here

1. Read references/repo-provenance.md to check whether this skill still matches the current checkout.
2. Read references/cli-reference.md for the main console commands.
3. Read the owning sub-skill for the workflow you want to run.

Common entry points

• Build vocabulary: onmt_build_vocab
• Train: onmt_train
• Translate: onmt_translate
• Serve: onmt_server
• Average models: onmt_average_models
• Release models: onmt_release_model

When to read the bundled references

• references/workflows.md for a quick route overview and the standard quickstart sequence.
• references/compatibility.md for backend, Python, and optional-dependency notes.
• references/troubleshooting.md for install, import, CUDA, config, and runtime failures.