Scoring decisions to ask or act reveals gaps in BFCL benchmarks

Asking Earns Nothing: Scoring the Decision to Act in BFCL Multi-Turn

Artificial Intelligence

Summary

Sometimes an AI assistant needs to decide if it should ask for more information or take action immediately. The authors studied a popular benchmark called BFCL multi-turn and found its scoring system doesn't reward asking questions properly. They created a new way to score these decisions directly, showing that some models that score well officially actually make worse decisions about asking. Their work includes a new scorer and carefully checked problem pairs to better evaluate when an AI should act or ask.

What this means in practice

  • For dialogue system developers: Assess AI agents’ ability to decide when to ask for more information versus acting immediately using an improved scoring method for BFCL multi-turn outputs.
  • For customer support bot teams: Improve training and evaluation of automated support agents by better distinguishing when bots should ask clarifying questions to avoid incorrect actions.

Authors

Yangze Liu, Zhongyi Han

Abstract

An agent that lacks the information it needs should ask rather than act, and the task definitions of agent leaderboards say so. BFCL multi-turn builds two of its four categories around a turn on which the model is supposed to ask, and its scorer never looks at that turn: the gold trajectory there is empty, the checker skips it, and the scripted user cannot answer, so asking earns nothing, guessing costs nothing on that turn, and asking twice loses the item. The benchmark also contains the control experiment for that decision. A should-ask item is a base item with one piece of information removed from one turn, so the same request appears twice at the same turn index, once complete and once not: on the first the model should make the call that changes the world, on the second it should ask. We score one decision per pair, whether the model attempted a world-changing call on that turn, read off the stored trajectories with no LLM judge; acting always and asking always both score 50. On the 223 pairs that pose this decision, gpt-5.4 attempts the call on 83.4% of the complete turns and holds back on 78.0% of the incomplete ones, the best decision accuracy of seven models at 80.7%; on the same items the official score ranks it sixth and puts first a model that lands in the middle here. One added line telling gpt-5.4 not to ask pushes it toward acting on both sides of the pair, so its decision accuracy shows no detectable change, while its official score rises by 13.5 to 23.5 points on the two should-ask categories and on the base twins; the opposite line, telling gemma-4-31B-it to ask first, improves its decision by 4.5 points and gains no official score. The score moves with the push toward action, not with the decision. We release the pairs, a turn-level scorer that runs on any BFCL output directory without an API key, and 31 manually verified bad items.