Temp-R1: A Unified Autonomous Agent for Complex Temporal KGQA via Reverse Curriculum Reinforcement Learning
Paper · 2026 · Zhaoyan Gong, Zhiqiang Liu, Songze Li et al.
Summary
Temp-R1 addresses question answering over temporal knowledge graphs (TKGQA), where facts are timestamped quadruples and questions often combine multi-hop links with time constraints. Earlier LLM-based systems use hand-designed pipelines with separate planners, retrievers and generators. They also depend on costly closed-source APIs. The authors instead train a single 8B open model as an autonomous agent using reinforcement learning (GRPO), after a short SFT cold start. Search-R1-style agents put all reasoning in one <think> block. Temp-R1 instead splits it into separate internal actions, <plan>, <filter> and <rank>, alongside the external <search> call to the TKG and a final <answer>. To keep the agent from relying on shortcuts that only work for easy questions, training follows a reverse curriculum: the hardest questions come first, then the easier ones. The agent reaches state-of-the-art results on MultiTQ and TimelineKGQA and beats GPT-4o-based methods. This shows that a small, cheap model can learn flexible temporal reasoning without a fixed workflow.
Key points
- Action space: an external
<search>action over the TKG, plus internal<plan>,<filter>(semantic and temporal constraints) and<rank>(chronological ordering) actions. These separate steps aim to reduce the hallucinations caused by overloading a single reasoning step. - Training pipeline: SFT warmup, then GRPO with a hard-first curriculum. Without SFT, training collapsed and KL loss spiked. Easy-first ordering plateaued early.
- On complex "Multiple"-type questions, Temp-R1 improves by 19.8% over the strongest baseline. It is evaluated on three datasets, including MultiTQ and TimelineKGQA.
- Backbones: peak accuracy was 0.790 for the 7B Qwen model versus 0.532 for 1.5B, and Llama reached 0.780. On complex questions the agent used more steps (
<think>rose from 1.36 to 2.93,<search>from 1.33 to 1.92). - Code is released at github.com/zjukg/Temp-R1. The authors note two limitations: experiments go only up to 8B, and the generality of reverse curriculum outside TKGQA has not been tested.
Institutions
Fields, topics and concepts
📚 Shelves 4The field of science this work belongs to (OpenAlex fields).Computer Science · 16,667 worksArtificial Intelligence · 16,194 worksArts and Humanities · 16,039 worksLanguage and Linguistics · 15,891 works
Cite
Cite as Zhaoyan Gong, Zhiqiang Liu, Songze Li, Xiaoke Guo, Yuanxiang Liu, Xinle Deng, Zhizhen Liu, Lei Liang, Huajun Chen and Wen Zhang. 2026. Temp-R1: A Unified Autonomous Agent for Complex Temporal KGQA via Reverse Curriculum Reinforcement Learning. Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers).
@inproceedings{gong2026temp,
title = {{Temp-R1: A Unified Autonomous Agent for Complex Temporal KGQA via Reverse Curriculum Reinforcement Learning}},
author = {Zhaoyan Gong, Zhiqiang Liu, Songze Li, Xiaoke Guo, Yuanxiang Liu, Xinle Deng, Zhizhen Liu, Lei Liang, Huajun Chen and Wen Zhang},
booktitle = {Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)},
year = {2026},
doi = {10.18653/v1/2026.acl-long.1184},
url = {https://doi.org/10.18653/v1/2026.acl-long.1184}
}References
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