Abstract <p>The work presents a hybrid neuro-symbolic method that combines a large language model (LLM) and a finite-state transducer (FST) to ensure morphological correctness in text generation for agglutinative languages. The system automatically extracts rules from corpus data: for local examples of word forms, the LLM produces sequences of morphological analyses, which are then aggregated and organized into compact descriptions of morphotactic rules (LEXC) and allomorph selection (regex). During generation, the LLM and FST operate jointly: if a token is not recognized by the automaton, the LLM derives a “lemma + tags” pair from the context, and the FST produces the correct surface form. A literary corpus (~1600 sentences) was used as the dataset. For a list of 50 nouns, 250 word forms were extracted. Using the proposed algorithm, the LLM generated 110 context-sensitive regex rules along with LEXC morphotactics, from which an FST was compiled that recognized 170/250 forms (~70%). In an applied machine translation test on a subcorpus of 300 sentences, integrating this FST into the LLM cycle improved quality from BLEU 16.14/ChrF 45.13 to BLEU 25.71/ChrF 50.87 without retraining the translator. The approach scales to other parts of speech (verbs, adjectives, etc.) as well as to other agglutinative and low-resource languages, where it can accelerate the development of lexical and grammatical resources.</p>