FLAIRR-TS - Forecasting LLM-Agents with Iterative Refinement and Retrieval for Time Series

Gunjan Jalori, Preetika Verma, Sercan O Arik


Abstract
Time series Forecasting with large language models (LLMs) requires bridging numerical patterns and natural language. Effective forecasting on LLM often relies on extensive pre-processing and fine-tuning. Recent studies show that a frozen LLM can rival specialized forecasters when supplied with a carefully engineered natural-language prompt, but crafting such a prompt for each task is itself onerous and ad-hoc. We introduce FLAIRR-TS, a test-time prompt optimization framework that utilizes an agentic system: a Forecaster-agent generates forecasts using an initial prompt, which is then refined by a refiner agent, informed by past outputs and retrieved analogs. This adaptive prompting generalizes across domains using creative prompt templates and generates high-quality forecasts without intermediate code generation. Experiments on benchmark datasets show FLAIRR-TS improves forecasting over static prompting and retrieval-augmented baselines, approaching the performance of specialized prompts.FLAIRR-TS provides a practical alternative to fine-tuning, achieving strong performance via its agentic approach to adaptive prompt refinement and retrieval.
Anthology ID:
2025.findings-emnlp.834
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2025
Month:
November
Year:
2025
Address:
Suzhou, China
Editors:
Christos Christodoulopoulos, Tanmoy Chakraborty, Carolyn Rose, Violet Peng
Venue:
Findings
SIG:
Publisher:
Association for Computational Linguistics
Note:
Pages:
15427–15437
Language:
URL:
https://preview.aclanthology.org/author-page-yu-wang-polytechnic/2025.findings-emnlp.834/
DOI:
10.18653/v1/2025.findings-emnlp.834
Bibkey:
Cite (ACL):
Gunjan Jalori, Preetika Verma, and Sercan O Arik. 2025. FLAIRR-TS - Forecasting LLM-Agents with Iterative Refinement and Retrieval for Time Series. In Findings of the Association for Computational Linguistics: EMNLP 2025, pages 15427–15437, Suzhou, China. Association for Computational Linguistics.
Cite (Informal):
FLAIRR-TS - Forecasting LLM-Agents with Iterative Refinement and Retrieval for Time Series (Jalori et al., Findings 2025)
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PDF:
https://preview.aclanthology.org/author-page-yu-wang-polytechnic/2025.findings-emnlp.834.pdf
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