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Guarded progressive ramp: An error rate equal to the threshold rolls back · case 04

Launches sitting exactly at the tolerated 2 percent error rate are rolled back.

Member previewVariant 4 · 3 implementations · 8 checks per implementation

Case contract

stages is an increasing list of percentages; the ramp starts at stages[0]. Each check [error_rate, sample] is processed in order: after a rollback everything stays at 0; a sample below 100 holds the current stage; an error rate above 0.02 rolls back to 0 permanently; otherwise advance one stage (staying at the last). State is complete at the last stage, rolled_back after a rollback, else ramping. Return [final percent, state, percent after each check].

Why this case matters

Automated ramps with guardrails must neither overreact to noise nor resume after a rollback.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
guardrail sample 28	`[0, "rolled_back", [0, 0, 0, 0, 0]]`	`[0, "rolled_back", [100, 100, 100, 0, 0]]`	Failed

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