PRFC: Learning Progressive Recovery from Function Calling Errors for Tool-Using LLMs

Beibei Yu, Tao Shen, Ling Chen


Abstract
Tool-using large language models (LLMs) can make multiple attempts to complete a task, using execution feedback from failed tool calls to identify errors and revise subsequent actions. However, their recovery performance often plateaus in later attempts, as models may repeat similar tool-call errors instead of making effective corrections. To address this limitation, we introduce PRFC, a reinforcement learning method that models error recovery as a sequential decision-making process. PRFC uses a progress-aware reward that assigns credit only when a later attempt improves upon previous failures, encouraging steady improvement across the recovery trajectory. Across four benchmarks with a Qwen3-4B backbone, PRFC improves multi-turn recovery on BFCL-v3 by an absolute 6.4% and achieves the highest mean score across three single-step tasks (API-Bank, T-Eval, and Nestful). These results show that modeling progress across attempts provides an effective learning signal for multi-attempt tool-use recovery. These results suggest that explicitly modeling progress across attempts provides a useful learning signal for tool-use recovery.
Anthology ID:
2026.findings-emnlp.1762
Volume:
Findings of the Association for Computational Linguistics: EMNLP 2026
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Hung-Yi Lee, Sunipa Dev, Jessy Li, Desmond Elliott
Venue:
Findings
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
37685–37706
Language:
URL:
https://aclanthology.org/2026.findings-emnlp.1762/
DOI:
10.18653/2026.findings-emnlp.1762
Bibkey:
Cite (ACL):
Beibei Yu, Tao Shen, and Ling Chen. 2026. PRFC: Learning Progressive Recovery from Function Calling Errors for Tool-Using LLMs. In Findings of the Association for Computational Linguistics: EMNLP 2026, pages 37685–37706, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
PRFC: Learning Progressive Recovery from Function Calling Errors for Tool-Using LLMs (Yu et al., Findings 2026)
Copy Citation:
PDF:
https://aclanthology.org/2026.findings-emnlp.1762.pdf