Pre-Mortem — Risk Assessment Gate

INTERNAL SKILL — This skill is now part of the /weave orchestrator. Use /weave instead for the full graph-first workflow. Direct invocation is deprecated and may be removed in a future release.

Trigger: When claiming a feature, epic, or any task touching risky domains (auth, payments, migrations, infrastructure, refactors).

Purpose: Address failure mode #1 (no risk assessment). Forces prospective hindsight — imagine the task has failed, then work backward to identify what went wrong.

Instructions

When invoked with a node ID (/pre-mortem <wv-id>):

1. Imagine Failure

Ask: "It's one week from now. This task has failed badly. What went wrong?"

Generate 3-5 failure scenarios:

•Technical failures (breaks existing functionality)
•Integration failures (doesn't work with other systems)
•Scope failures (takes 10x longer than expected)
•Data failures (corruption, loss, inconsistency)
•Security failures (vulnerabilities introduced)

2. Assess Each Risk

For each failure scenario, evaluate:

Factor	Scale	Description
Impact	low/medium/high/critical	How bad if it happens?
Likelihood	low/medium/high	How likely to occur?
Detectability	easy/medium/hard	Will we notice before production?

Priority = Impact × Likelihood (high-high = critical path risk)

3. Define Mitigations

For high-priority risks:

•Prevention: How to avoid the failure
•Detection: How to catch it early (tripwire)
•Recovery: How to roll back if it happens

4. Identify Blast Radius

What could be affected if something goes wrong?

•Files/modules touched
•Users/services impacted
•Data at risk
•Downstream dependencies

5. Create Rollback Plan

Before any changes:

•How to revert to working state?
•What's the backup strategy?
•Who needs to be notified?

6. Record in Metadata

bash

wv update <id> --metadata='{
  "risks": [
    {
      "scenario": "Database migration corrupts user data",
      "impact": "critical",
      "likelihood": "medium",
      "mitigation": "Backup before migration, test on staging first",
      "tripwire": "Row count mismatch after migration"
    }
  ],
  "blast_radius": ["users table", "auth service", "all logged-in users"],
  "rollback_plan": "Restore from pre-migration backup within 15 minutes"
}'

Output Format

Example output:

Task: wv-a1b2 — Migrate user sessions to Redis

Failure Scenarios:

•
[CRITICAL] Session data lost during migration
- •Impact: critical | Likelihood: medium
- •Mitigation: Export all sessions before, verify counts after
- •Tripwire: Session count drops by >5%
•
[WARNING] Redis connection failures under load
- •Impact: high | Likelihood: low
- •Mitigation: Connection pooling, fallback to old system
- •Tripwire: Connection timeout errors in logs
•
[LOW] Migration takes longer than maintenance window
- •Impact: medium | Likelihood: low
- •Mitigation: Test migration time on staging data
- •Tripwire: Progress <50% at halfway point

Blast Radius: auth-service, api-gateway, all active users

Rollback Plan: Revert config to use SQLite, sessions recreated on next login

Recommendation: Run on staging with production data copy first

NEVER

•Skip risk assessment for "simple" changes to shared infrastructure
•Start implementation without identifying rollback plan
•Ignore medium-likelihood critical-impact risks
•Assume "it worked in dev" means it will work in production

ALWAYS

•Run pre-mortem for any task with type=feature or type=epic
•Run pre-mortem for tasks touching: auth, payments, database, infrastructure
•Identify at least one tripwire (early warning sign)
•Define rollback plan before making changes

Risk Domains (Auto-Trigger)

These domains should always trigger pre-mortem:

•Authentication/Authorization — Security implications
•Payments/Billing — Financial implications
•Database migrations — Data integrity
•Infrastructure/DevOps — System availability
•Large refactors — Regression potential
•Third-party integrations — External dependencies
•User data handling — Privacy implications

Integration

This skill is called by:

•/fix-issue — Before implementation for significant tasks
•Pre-claim hook — Auto-invokes for features/epics and risky domains
•/battle-plan — Part of planning sequence

Examples

Example 1: Auth Change

bash

/pre-mortem wv-b2c3

# Task: Add OAuth2 provider

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

# Risks:

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

#   1. Breaks existing email/password login (critical/low)

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

#   2. OAuth tokens stored insecurely (critical/medium)

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

#   3. Callback URL misconfiguration (high/medium)

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

# Blast radius: All users, login flow, session management

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

# Rollback: Feature flag to disable OAuth, revert to password-only

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

Example 2: Database Migration

bash

/pre-mortem wv-d4e5

# Task: Add indexes to users table

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

# Risks:

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

#   1. Table lock during index creation (high/high)

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

#   2. Disk space exhaustion (medium/low)

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

#   3. Query planner changes break existing queries (medium/medium)

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

# Blast radius: users table, all user-related queries

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

# Rollback: DROP INDEX, restore query performance

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

# Mitigation: Use CONCURRENTLY, run during low traffic

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

Example 3: Refactor

bash

/pre-mortem wv-f6g7

# Task: Extract shared utilities to new package

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

# Risks:

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

#   1. Import path changes break consumers (high/high)

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

#   2. Circular dependency introduced (medium/medium)

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

#   3. Build time increases significantly (low/medium)

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

# Blast radius: All packages importing utilities

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

# Rollback: Revert package extraction, inline utilities

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

# Mitigation: Update all imports in same PR, test full build

> **INTERNAL SKILL** — This skill is now part of the `/weave` orchestrator.
> Use `/weave` instead for the full graph-first workflow.
> Direct invocation is deprecated and may be removed in a future release.

Metadata Schema

json

{
  "risks": [
    {
      "scenario": "Brief description of failure",
      "impact": "low|medium|high|critical",
      "likelihood": "low|medium|high",
      "detectability": "easy|medium|hard",
      "mitigation": "How to prevent or reduce",
      "tripwire": "Early warning sign"
    }
  ],
  "blast_radius": ["affected systems/files/users"],
  "rollback_plan": "How to revert if needed",
  "pre_checks": ["Verification before starting"],
  "risk_level": "low|medium|high|critical"
}

Decision Gate

After pre-mortem, decide:

•Proceed: Risks are acceptable and mitigated
•Reduce scope: Too risky, simplify approach
•Defer: Need more information or preparation
•Escalate: Requires stakeholder input on risk acceptance

Related Skills

•/ship-it — Define done criteria (pairs with risk assessment)
•/wv-verify-complete — Verify mitigations worked
•/sanity-check — Validate assumptions about risks