The dataset for LLM fine-tuning is organized as text documents with prompt-output pairs, see Figure , more examples of promptoutput pairs are in the SI †. The prompt includes the set prefix and a text description of the structure. For transformed structures, each text description is appended with a description of the performed transformation. The output includes code and CIF with structure in conventional representation. With this dataset format, we tested two versions of the model: one that prints only the code ("text-code") and one that prints both the code and the structure as a CIF file ("text-code-CIF").