In multi-agent IR pipelines for tasks such as search and ranking, LLM-based agents exchange intermediate reasoning in terms of Chain-of-Thought (CoT) with each other. Current CoT evaluation narrowly focuses on target task accuracy. However, this metric fails to assess the quality or utility of the reasoning process itself. To address this limitation, we introduce two novel measures: reusability and verifiability. We decouple CoT generation from execution using a Thinker-Executor framework. Reusability measures how easily an Executor can reuse the Thinker's CoT. Verifiability measures how frequently an Executor can match the Thinker's answer using the CoT. We evaluated four Thinker models against a committee of ten Executor models across five benchmarks. Our results reveal that reusability and verifiability do not correlate with standard accuracy, exposing a blind spot in current accuracy-based leaderboards for reasoning capability. Surprisingly, we find that CoTs from specialized reasoning models are not consistently more reusable or verifiable than those from general-purpose LLMs like Llama and Gemma.
Figures & tables
Figure 1. Reusability Flowchart Flowchart showing how CoTs from correct answers of Thinker go to Executor and help/harm them to be counted towards reusability
Dataset
Executor
Thinker Model
Gemma
Llama
Phi
R1
GSM8K
Full Comm.
66.04
73.46
83.53
66.56
Strong Comm.
80.75
87.82
94.68
84.54
Weak Comm.
51.33
59.10
72.37
48.59
StrategyQA
Full Comm.
42.13
43.35
45.25
44.58
Strong Comm.
44.53
45.87
51.57
48.88
Table 1. Reusability Score across Datasets and Committees
Dataset
Executor
Thinker Model
Gemma
Llama
Phi
R1
GSM8K
Full Comm.
79.46
71.33
88.36
80.33
Strong Comm.
91.48
82.97
97.82
93.37
Weak Comm.
67.45
59.70
78.91
67.29
StrategyQA
Full Comm.
57.05
44.98
58.52
61.64
Strong Comm.
64.02
51.44
63.20
69.11
Table 2. Verifiability Score across Datasets and Committees
Weak vs Strong
Strong vs Full
Full vs Weak
Dataset
GSM8K
0.6667
1.0000
0.6667
StrategyQA
-0.3333
1.0000
-0.3333
SVAMP
0.6667
1.0000
0.6667
ARC
0.6667
1.0000
0.6667
CommonSenseQA
1.0000
1.0000
1.0000
Table 3. Kendall’s τ correlation of rankings based on reusability scores across weak, strong, and full committees.
Weak vs Strong
Strong vs Full
Full vs Weak
Dataset
GSM8K
0.6667
1.0000
0.6667
StrategyQA
0.6667
0.6667
1.0000
SVAMP
0.6667
1.0000
0.6667
ARC
0.6667
0.6667
1.0000
CommonSenseQA
0.6667
0.6667
1.0000
Table 4. Kendall’s τ correlation of rankings based on verifiability scores across weak, strong, and full committees.
Model Name
GSM8K
StrategyQA
SVAMP
ARC
CommonSenseQA
A
R
V
A
R
V
A
R
V
A
R
V
A
R
V
Gemma3
93
66
79
94
42
57
93
39
79
93
36
50
80
41
34
Llama3.1
78
73
71
71
43
45
82
65
72
83
43
47
68
43
37
Phi4-Reasoning
81
84
88
95
45
59
90
44
89
81
43
70
70
44
70
DeepSeek-R1
94
67
80
93
45
62
95
34
80
95
32
63
82
32
60
Table 5. Model Performance Metrics across Multiple Datasets (Rounded to nearest integer)
Dataset
A vs R
R vs V
V vs A
GSM8K
-0.33
0.33
0.33
StrategyQA
0.33
0.33
0.33
SVAMP
-1.00
-0.33
0.33
ARC
-1.00
0.00
0.00
CommonSenseQA
-0.67
0.33
0.00
Average
-0.53
0.13
0.20
Table 6. Kendall τ correlation between evaluation metrics (A=Accuracy, R=Reusability, V=Verifiability) across Datasets.
Applied Agent Research Center, Korea Institute of Science and Technology Information (KISTI), Republic of Korea · Department of Computer Science and Engineering, University of Seoul, Republic of Korea.