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name: cot_equation_calculator description: Safely check and repair simple arithmetic equations inside chain-of-thought reasoning traces.

Chain-of-Thought Equation Calculator

Use this skill when an arithmetic chain-of-thought trace contains explicit equations and you need to verify or repair calculation-only errors. Do not use it to validate semantic reasoning, create prompts, or score final answers directly.

Inputs

• Reasoning text containing equation-like spans such as 2 * 3 = 6.
• Optional repair flag.
• Optional operator and expression-length bounds.

Outputs

• Equation check records with expression, stated result, computed result, and correctness.
• Aggregate correctness flag.
• Optional repaired text that changes only incorrect stated numeric results.

Workflow

1. Find simple equation spans in the reasoning trace.
2. Parse arithmetic expressions with Python ast.
3. Allow only numeric constants and arithmetic operators.
4. Compare computed and stated results.
5. If repair is requested, replace only the stated numeric result for safe equations.

Validation

Run:

python scripts/cot_equation_calculator.py --self-test
python -m unittest discover -s tests

The tests cover correct equations, incorrect equations, repaired traces, multiple equations, and unsafe expressions that must be ignored.

Limitations

The calculator intentionally refuses variables, function calls, and arbitrary Python syntax. It cannot decide whether the chosen equation is semantically appropriate for the word problem.