  We introduce API Pack, a massive multi-programming language dataset
containing more than 1 million instruction-API call pairs to improve the API
call generation capabilities of large language models. By fine-tuning
CodeLlama-13B on 20,000 Python instances from API Pack, we enable it to
outperform GPT-3.5 and GPT-4 in generating unseen API calls. Fine-tuning on API
Pack also facilitates cross-programming language generalization by leveraging a
large amount of data in one language and small amounts of data from other
languages. Scaling the training data to 1 million instances further improves
the model's ability to generalize to new APIs not used in training. To
facilitate further research, we open-source the API Pack dataset, trained
model, and associated source code at https://github.com/zguo0525/API-Pack.
