ToolMATH: A Diagnostic Benchmark for Long-Horizon Tool Use under Systematic Tool-Catalog Constraints
Organizations: Seoul National University
Abstract
We introduce \ToolMATH, a math-grounded diagnostic benchmark for evaluating long-horizon tool use under controllable tool-catalog conditions. \ToolMATH converts stepwise MATH solutions into reusable Python tools with natural-language descriptions and typed schemas, and pairs each problem with a tool environment requiring sequential tool use, intermediate-output reuse, and logically connected tool-call chains. \ToolMATH controls tool availability and catalog difficulty by constructing gold tools and graded distractors with varying similarity to gold tools. \ToolMATH also incorporates behavior-conditioned metrics, enabling diagnostic evaluation beyond final accuracy. Building on these measurements, \ToolMATH emphasizes three evaluation axes: (1) Adaptability measures how much Gold-only success is retained when gold tools are replaced entirely by distractors; (2) Robustness measures stability under adding distractors as a noise; and (3) Tool Connectivity measures whether models preserve accuracy over long executed tool-call chains. Furthermore, trace-level failure analyses characterize how models fail under each tool-catalog condition. Together, these diagnostics reveal distinct model profiles: reliable tool use, tool avoidance, adaptive substitution, and impacts of unreliable tool catalogs. Overall, \ToolMATH provides a controlled testbed for evaluating how language models adapt to changing tool availability, remain robust to distractors, and maintain correctness across long-horizon tool-use trajectories.
Figures & tables
| Model | Condition | Accuracy | Tool-Acc | NoTool-Acc | Tool-call rate |
|---|---|---|---|---|---|
| Claude-4.6 | Gold-only | 98.4 | 97.9 | 99.5 | 65.6 |
| Claude-4.6 | Gold-present | 97.8 | 96.5 | 99.4 | 67.8 |
| Claude-4.6 | Distractors-only | 97.8 | 98.1 | 97.8 | 15.2 |
| Gemini-3.1-Pro | Gold-only | 99.2 | 90.4 | 99.7 | 5.4 |
| Gemini-3.1-Pro | Gold-present | 99.0 | 97.7 | 99.3 | 18.9 |
| Gemini-3.1-Pro | Distractors-only | 98.9 | 99.4 | 98.8 | 17.6 |
| Model | Adaptability | Rob.(L1) | Rob.(L2) | Rob.(L3) | Rob.(L4) | Rob.(L5) | Robustness Avg. |
|---|---|---|---|---|---|---|---|
| GPT-4o-mini | 59.68 | 89.95 | 89.64 | 89.44 | 90.84 | 89.61 | |
| Llama3-8B | 8.63 | 66.07 | 67.65 | 66.82 | 77.20 | 72.95 | |
| Qwen2.5-7B | 65.12 | 94.29 | 94.81 | 90.32 | 89.55 | 86.91 |
Appendix figures & tables15 assets
Supplementary material from the paper’s appendix.
Appendix
| Label | Definition |
|---|---|
| Plan Error ( ) | The initial plan is ineffective (logically incorrect, or missing essential steps/subgoals). |
| Tool Selection Error ( ) | At least one call selects an irrelevant tool or fails to use a suitable tool for a subproblem. |
| Tool Hallucination ( ) | At least one call references a tool name that does not exist in the provided tool list. |
| Wrong Parameter Value ( ) | At least one call uses schema-valid argument types but incorrect/irrelevant values (e.g., wrong constants/inputs, mismatched intermediate values). |
| Formatting Error ( ) | At least one call violates the input schema or fails JSON conversion (e.g., wrong types/missing fields, malformed JSON, tool calls in plain text). |
| Thought Error ( ) | Reasoning is incorrect given the final answer/tool logic, contradicts observations, or hallucinates Action / Observation to bypass interaction. |