Learn: Post-Incident Review, Purple Teaming and Detection Debt

All courses / AI Blue / Module 2 / Chapter 11

Learning objectives

After the lesson the participant can:

Facilitate a blameless review that ends in at most three committed changes with re-tests
Apply the five rules that keep an AI-drafted review honest
Trace a finding through the six stages from opening to control classification
Assess detection and playbook debt against thresholds and explain the measures of learning and how each is gamed

Key concepts

Blameless review: A review that asks what made the actions of people and systems reasonable at the time and treats the conditions as the object of change. It lists contributing conditions, not causes, and names nobody as a cause.
Finding: A statement that a control, a detection, a playbook, a mandate, a contract term or a skill did not hold in a stated condition. It is closed only when the re-test passes, not when the change is merged.
Re-test designed at opening: The re-test is defined when the finding is opened, not when the change is merged, because a re-test written after the fix tends to test the fix.
Purple loop: The joint loop between the red team and the blue team: an exercise yields techniques tried and whether a detection fired, and every detection built from it carries the exercise scenario as a regression test.
Playbook and mandate debt: A rollback or stop path not exercised for 180 days lowers the autonomy ceiling one level until exercised; a mandate past its review date makes the agent's permissions lapse at the policy decision point.

Interactive exercises

Do them here and get feedback at once. Choose a card and then where it belongs, or drag it.

Interactive exercise 1 · Put in order

From finding to verified control

Put the six stages of the chapter's finding-to-control path in order.

Interactive exercise 2 · Match

How each measure of learning is gamed

Match each measure of learning with the way the chapter says it can be gamed.

Teaching plan

15 min	Teacher presents review as engineering and the 90-minute method, with its ground rules and the limit of three changes.
15 min	Reading of PIR-HM-0455: participants identify which sections an AI system drafted, who verified them and how each of the three findings is tied to a re-test.
45 min	Exercise: groups run a compressed blameless review of the 2027-04-12 incident or of an incident of their own and open the findings.
15 min	Input and questions on the purple loop, chaos experiments and the debt thresholds table.
15 min	Plenary on measuring learning: each group picks one measure and explains how it could be gamed and the counter-measure.

Discussion

A draft timeline that needs no corrections over several reviews is a signal to seed an error. Why might a perfect draft be a warning rather than a success?
The chapter concludes that the rate of new detections is bounded by the rate at which the team can test them. What follows for a team whose drafting assistant is very productive?
Nordvik Region learns mainly through contracts and the few rules it owns. What does a re-test look like when the change is a contract term and not code?

Written exercise

Exercise · 45 minutes

A blameless review with three changes

Run the 90-minute method in compressed form on the incident of 2027-04-12 at Hansa Mutual's Polish service centre, where a legitimate scheduler rollout was contained, or on an incident of your own. Appoint a facilitator who was not the incident commander and a scribe. State the ground rules, walk the timeline once and record every correction. For each decision point, list what the person or system knew and the contributing conditions. Choose at most three changes; give each an owner who is a role, a due date, the artefact it changes and the re-test that re-runs the original scenario. Record what the team decided not to do and why, and mark any section an AI system drafted.

Deliverable: A post-incident review record with corrected timeline, contributing conditions, three findings with owner, date, artefact and re-test, and decisions not taken.

Your work

Self-test

Choose an answer to see whether it is right, or open the answer below each question.

When is a finding closed, according to the rule the chapter takes over from AI Red Team, Chapter 26?
Show the answer
C. When the re-test that re-runs the original scenario has passed
A finding is not closed because the change was merged but because the re-test passed. The re-test is designed when the finding is opened.
What is the default consequence when a mandate passes its review date?
Show the answer
A. The agent's permissions lapse at the policy decision point
The threshold for a mandate past its review date is zero days: an expired mandate does not keep running. A ceiling drop is the consequence for an unexercised rollback or stop path.
Which of the chapter's five rules governs what an AI system may read when it drafts a review?
Show the answer
B. It may read the evidence pack and nothing else; unsupported statements are struck out
The evidence pack is the authority and the draft is a view of it. AI proposes changes at Level 1 Assisted; the choice of the three changes belongs to the review, which is never a performance assessment.