JSON Whisperer: Efficient JSON Editing with LLMs

Sarel Duanis, Asnat Greenstein-Messica, Eliya Habba


Abstract
Large language models (LLMs) can modify JSON documents through natural language commands, but current approaches regenerate entire structures for each edit, resulting in computational inefficiency. We present JSON Whisperer, a framework that enables LLMs to generate RFC 6902 diff patches-expressing only the necessary modifications-rather than complete documents.We identify two key challenges in patch-based editing: (1) LLMs often miss related updates when generating isolated patches, and (2) array manipulations require tracking index shifts across operations, which LLMs handle poorly. To address these issues, we introduce EASE (Explicitly Addressed Sequence Encoding), which transforms arrays into dictionaries with stable keys, eliminating index arithmetic complexities.Our evaluation shows that patch generation with EASE reduces token usage by 31% while maintaining edit quality within 5% of full regeneration with particular gains for complex instructions and list manipulations.
Anthology ID:
2025.emnlp-industry.88
Volume:
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing: Industry Track
Month:
November
Year:
2025
Address:
Suzhou (China)
Editors:
Saloni Potdar, Lina Rojas-Barahona, Sebastien Montella
Venue:
EMNLP
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
1265–1274
Language:
URL:
https://preview.aclanthology.org/ingest-emnlp/2025.emnlp-industry.88/
DOI:
Bibkey:
Cite (ACL):
Sarel Duanis, Asnat Greenstein-Messica, and Eliya Habba. 2025. JSON Whisperer: Efficient JSON Editing with LLMs. In Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing: Industry Track, pages 1265–1274, Suzhou (China). Association for Computational Linguistics.
Cite (Informal):
JSON Whisperer: Efficient JSON Editing with LLMs (Duanis et al., EMNLP 2025)
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PDF:
https://preview.aclanthology.org/ingest-emnlp/2025.emnlp-industry.88.pdf