Trajectory-Level Speculation with Semantic Verification for Tool-Using Agents
We introduce SpecAgent, a collaboration protocol that turns the strong model from the author of each step into a reviewer of steps drafted by a weak model.
ProofPaper ↗
Key points
- Large language model agents solve tasks through long sequences of tool calls, and the prevailing design has a single strong model generate every step, although many steps are routine enough for a much smaller model.
- Existing ways of sharing this work keep the strong model as the generator: routers and collaborative agents decide which model handles each query or step, and speculative methods check a small model's drafts one step at a time, usually against the strong model's own action.
- On $τ^2$-Bench, SpecAgent comes within one point of the strong model's success rate while roughly halving memory traffic and wall time, and on AutomationBench and VitaBench it recovers 44-75% of the quality gap while lowering both.
- These results suggest that a strong model need not author every step of an agent: reviewing grounded drafts retains most of its quality while cutting both latency and memory traffic.
Sources (2)
- [1]Trajectory-Level Speculation with Semantic Verification for Tool-Using AgentsarXiv (AI, ML, NLP, CV, robotics, multi-agent) · Oct 15, 08:06 AM
We introduce SpecAgent, a collaboration protocol that turns the strong model from the author of each step into a reviewer of steps drafted by a weak model.
Large language model agents solve tasks through long sequences of tool calls, and the prevailing design has a single strong model generate every step, although many steps are routine enough for a much smaller model.
- [2]Trajectory-Level Speculation with Semantic Verification for Tool-Using AgentsHugging Face Daily Papers · Oct 15, 12:00 AM · same content
Extractive summary: sentences quoted from the sources.
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