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---
description: Conduct post-incident review with root cause and improvement actions
---
# Lessons Learned
Conduct a blameless post-incident review for "$ARGUMENTS" with incident timeline, root cause analysis, contributing factors, and corrective actions at three levels.
## Prerequisites
Read `.metapowers/security/$ARGUMENTS/00-govern.md`. If this file does not exist, tell the user:
> Phase 0 (Govern) has not been completed for "$ARGUMENTS". Run a Govern skill first (e.g., `/security:security-policy $ARGUMENTS`), or use `--skip-checks` to bypass.
If `--skip-checks` is present in $ARGUMENTS, skip this check and log to `.metapowers/security/$ARGUMENTS/skip-log.md`.
## Process
1. **Read context files:**
- Read `plugins/security/shared/incident-response-template.md` for post-incident review reference
- Read `.metapowers/security/$ARGUMENTS/00-govern.md` for organizational context
- Read `.metapowers/security/$ARGUMENTS/04-respond.md` if it exists, for incident response context
2. **Facilitate blameless post-incident review:**
- Establish blameless culture ground rules: focus on systems and processes, not individuals
- Gather all responders and stakeholders for input
- Collect artifacts: logs, chat transcripts, alerts, tickets, and status updates from the incident
- Set review scope: what happened, how we responded, what we can improve
3. **Build incident timeline (detection to resolution):**
- Document each event chronologically with timestamps (UTC)
- Key milestones: initial trigger, detection, first response, containment, eradication, recovery, closure
- Note time gaps between milestones (detection delay, response delay, escalation delay)
- Identify who did what at each stage
- Calculate key metrics: time to detect (TTD), time to respond (TTR), time to contain (TTC), time to recover
4. **Apply 5 Whys for root cause analysis:**
- Start with the incident symptom and ask "Why?" iteratively
- Continue until reaching the systemic root cause (typically 3–5 levels deep)
- Document each level with supporting evidence
- Identify both the technical root cause and the process root cause
- Validate root cause: if this cause were fixed, would the incident have been prevented?
5. **Identify contributing factors:**
- **Process factors** — missing runbooks, unclear escalation paths, insufficient monitoring coverage
- **Technology factors** — misconfiguration, unpatched vulnerability, inadequate tooling, missing automation
- **People factors** — insufficient training, knowledge gaps, fatigue, unclear responsibilities (not blame)
- Map contributing factors to the timeline to show where each factor increased severity or delayed response
6. **Define corrective actions at three levels:**
- **Immediate fix** — address the specific vulnerability or gap that caused this incident (patch, config change, access revocation)
- **Prevent recurrence** — implement controls to prevent the same type of incident (automated scanning, additional monitoring, policy update)
- **Systemic improvement** — address the underlying organizational or architectural weakness (security architecture redesign, training program, process overhaul)
- Each action must have: description, owner, deadline, priority, and success criteria
7. **Assign owners and track completion:**
- Assign each corrective action to a named owner
- Set realistic deadlines (immediate fixes: 1 week, prevent recurrence: 1 month, systemic: 1 quarter)
- Define tracking mechanism (ticket system, review meetings)
- Schedule follow-up review to verify completion
- Escalate overdue actions
8. **Update playbooks based on findings:**
- Identify gaps in existing playbooks revealed by the incident
- Add new detection rules for indicators discovered during investigation
- Update communication templates if communication was ineffective
- Add decision tree entries for scenarios encountered
- Document new forensic data sources identified during investigation
9. **Write the artifact** to `.metapowers/security/$ARGUMENTS/04-respond.md` with heading:
## Lessons Learned
Include sections:
- **Incident Summary** — type, severity, duration, and impact
- **Timeline** — chronological event log with key metrics (TTD, TTR, TTC)
- **Root Cause Analysis** — 5 Whys analysis with supporting evidence
- **Contributing Factors** — process, technology, and people factors
- **Corrective Actions** — three-level action plan with owners and deadlines
- **Playbook Updates** — changes to existing playbooks and procedures
- **Metrics** — incident response performance metrics and trends
## Output
The lessons learned review written to `.metapowers/security/$ARGUMENTS/04-respond.md`. Present a summary to the user highlighting:
- Root cause identified through 5 Whys analysis
- Key contributing factors by category
- Corrective actions at all three levels with owners
- Playbook and process updates recommended