A 1.7B selector for leaf-level actions raised robot task completion from 60.5 to 68.5 percent and cut host-model tokens
AspireAI community · arXiv preprint
A recursive agent keeps asking its large model to do the same small job over and over: turning a familiar instruction into an executable action. LeafSkill points out that high-level planning is task-specific but leaf-level action grounding recurs, and measures it - in the authors' Robotouille and ALFWorld traces, grounding consumed 22.9%, 23.7% and 44.5% of host-model tokens. The fix is an external reuse layer that retrieves semantically related grounding experience, binds action templates to the objects and admissible actions actually present, and hands the choice to a lightweight 1.7B selector that can also abstain and let the original agent handle the subtask unchanged.
On Robotouille, success went from 60.5% to 68.5% (exact McNemar p = .0259) against ReCAP with a Qwen3.5-27B host, and host tokens dropped 23.09% on average on jointly solved tasks. The library could also grow from 446 to 588 skills with no selector retraining and no test trajectories.
Caveat: two environments, one host model, and ALFWorld success was statistically indistinguishable (90.3% vs 90.3%).
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