HindSearch: Trajectory-Level Hindsight Critique for Search-Augmented Reinforcement Learning¶
Core-mechanism mini-suite. Executes the search-trajectory hindsight operator. A small deterministic evaluation does not reproduce the full paper.
Paper information¶
| Field | Details |
|---|---|
| Paper | arXiv 2608.01597 |
| Organization | Santa Clara University |
| First public release | 2026-08-03 (arXiv v1) |
| Authors' code | https://anonymous.4open.science/r/hindsearch-anon-EBDC |
| Adapter / method | hindsearch |
| Local reproduction code | src/auto_research/agent_research/latest_20260809.py |
Original paper¶
Motivation and method¶
Topic: hindsight for search trajectories. A frozen judge uses gold answers to write trajectory-level critiques for failed searches. Sparse success/failure becomes auxiliary on-policy distillation, combined with GRPO.
Architecture¶
flowchart LR
N0["Search rollouts"] --> N1
N1["Final verifier"] --> N2
N2["Failed trajectory"] --> N3
N3["Gold-aware critique"] --> N4
N4["GRPO and distillation"]Key figure from the paper¶
Figure 2: Training flow and key optimization steps. From the original paper; copyright remains with the authors.
Core equation¶
\(\mathcal L=\mathcal L_{GRPO}+\lambda\mathcal L_{distill}(\pi_\theta,\text{critique})\).
Paper results¶
The paper reports consistent gains on search-augmented reasoning under its protocol. Local experiments do not present a gold-aware judge as deployed capability.
Local reproduction¶
See the stable metrics. Checkpoints and raw run directories are not committed.
auto-research agent-research --method hindsearch --benchmark planbench-mini --episodes 120 --seed 42
Local comparison: Compare HindSearch with a control without the mechanism in the same public mini-suite. Report only local artifact metrics; large-model and real-environment paper results are not local gains.
Reproduction boundaries¶
- Implements the paper-specific state, credit, or selection operator, not merely a renamed method.
- No original large model, proprietary environment, or expensive judge was run; these are not marked integrated.
- HindSearch participates in unified evolve candidate discovery. Composed genomes remain subject to public evaluation and budget constraints.