detect-breakpoint

Purpose

Locate the point or region where performance, validity, or a claim changes regime.

Input contract

required: [ordered_observations, target_metric, flip_or_regime_rule]
optional: [candidate_axis, smoothing_rule, uncertainty_bounds]
constraints: [ordering and metric direction are explicit]

Procedure

1. Sort observations along the declared axis and validate comparability.
2. Detect abrupt flips, slope changes, saturation, or regime transitions.
3. Estimate boundary region and attach uncertainty.
4. Return witness observations and follow-up tests.

Output contract

produces: [breakpoint_region, regime_label, witness_observations, uncertainty, follow_up_tests]
delta_fields: [findings, uncertainties, open_questions]