AI Agent Binary Search Debug 2026

When an Agent makes an error at step 7 of a 10-step task, tracing from the start is too slow, and tracing from the end is also slow. The binary search method is the fastest.

💡 What You Will Learn

When an Agent makes an error at step 7 of a 10-step task, tracing from the start is too slow, and tracing from the end is also slow. The binary search method is the fastest.

1 -> 2 -> 3 -> 4 -> 5 -> 6 -> 7 -> 8
                                        ^

4 -> 5-8
4 -> 1-4

class Checkpoint:
    def __init__(self):
        self.steps = []

    def record(self, step_name, input_data, output_data):
        self.steps.append({
            'step': step_name,
            'input': input_data,
            'output': output_data
        })

    def debug(self, failed_step):
        low, high = 0, len(self.steps) - 1
        while low < high:
            mid = (low + high) // 2
            if self.steps[mid]['output'] is None:
                high = mid
            else:
                low = mid + 1
        return self.steps[low]

Summary