Hypothesis-Differential Debugging

Overview

The scientific method's payoff for an agent is not narrating "observe -> question." It is the differential: when a symptom could come from several places, enumerate competing falsifiable hypotheses and spend your cheapest observation on the one that best discriminates between them.

This is the proven replacement for the old broad scientific-method skill. In SWE-bench fault localization, the original was flat; this agent-native version turned it into the strongest measured debugging lift in the current eval set.

Core Principle: Don't guess-and-patch. Enumerate competing causes, then make the cheapest observation that would falsify the most likely one.

When to Use

• A bug or incident symptom could plausibly come from more than one place
• You have read access to code, logs, diffs, traces, or tests
• You need to localize the faulty file, function, branch, config, or invariant before fixing