Premortem

Premortem

Imagine the plan already failed, then explain why. This "prospective hindsight" tense-shift (Klein, HBR 2007) generates ~30% more failure causes than asking "what could go wrong?" — and the causes are more specific. The skill turns that mechanism into a repeatable run that ends in a revised plan, not just a list of worries.

Workflow Routing

Trigger	Workflow
"premortem this", "run a premortem", "what could kill this", high-stakes plan	Workflows/RunPremortem.md (full: parallel deep-dive agents)
"quick premortem", small/personal decision, fast gut-check, thin context	Workflows/QuickPremortem.md (solo single-pass, no fan-out)
"update the premortem skill", add/fix a workflow	Workflows/Update.md

Default to RunPremortem for anything with real stakes. Drop to QuickPremortem only when the decision is small or the user explicitly wants speed.

The Mechanism (don't skip the framing)

The entire technique is one move: state that failure has already happened, with certainty, and ask what caused it. Everything else is delivery. If a step doesn't help the user inhabit "it already failed," cut it. Full evidence and citations: References/Methodology.md.

Quick Reference

• Frame in past tense. "It's [horizon]. [The plan] has failed. Here's why." Not "could fail."
• Generate causes independently first. In RunPremortem, parallel agents must NOT see each other's output — this is the anti-anchoring safeguard, and it is load-bearing.
• Demand plan-specific causes. Reject generic risks ("timeline slips"). Ground every cause in actual plan details.
• Always land on action. Each retained risk → a mitigation + an early-warning signal. End with a revised plan and a pre-launch checklist. A premortem with no follow-through is theater.
• Markdown is canonical. The transcript (.md) is the record. HTML is an optional visual artifact via Tools/GenerateReport.ts --html, never the primary output.

When NOT to run a premortem

• Vague concepts with no concrete plan — gather the plan first, or you'll generate generic risk.
• Decisions already irreversibly made — nothing to revise; value is low.
• Factual questions or creative feedback — wrong tool.
• Attacking an idea/argument in the abstract → RedTeam. Current multi-view debate → Council.

Tools

• Tools/GenerateReport.ts — turns a findings JSON (schema in References/Templates.md) into a markdown report (default) or a self-contained HTML report (--html). Run with bun. See Tools/GenerateReport.help.md.

Gotchas

The highest-density part of this skill. Add to it after every run that surprises you.

• The "30%" stat is about quantity, not correctness. The 1989 Mitchell/Russo/Pennington study found prospective hindsight produces ~30% more reasons generated — NOT 30% better at identifying the correct reasons. Klein's HBR paraphrase ("correctly identify") overstates it. Never tell a user the premortem makes them "30% more accurate." It makes them more prolific and specific. Citing it wrong makes the whole analysis look sloppy.
• Anchoring kills the run. If you generate causes sequentially (or let one agent see another's output), the first failure named frames everything after it. Generate independently, then merge. This is why RunPremortem fans out parallel agents and explicitly forbids cross-talk.
• Generic risks are the #1 quality failure. "Budget overruns," "team gets distracted," "market shifts" apply to every plan and help no one. If a cause would survive find-and-replace of the subject, it's too generic — force it to cite a real plan detail.
• Run it BEFORE commitment. A premortem after the money is spent and the team is emotionally bought in becomes a ritual. Its value is in changing the plan, so it needs a changeable plan.
• Don't confuse it with RedTeam or Council. Premortem = imagined future failure of a concrete plan, ending in a revised plan. RedTeam = adversarial attack on an arbitrary idea. Council = multiple current perspectives debating. Overlapping vocabulary, different mechanisms.
• Thin context → generic output. If you can't state (1) what's being premortemed in one sentence, (2) who's affected, (3) what success means, STOP and ask one question at a time. Don't generate failures from nothing — that produces exactly the generic risk this technique exists to avoid.
• Failure ≠ pessimism. The output is specific causal stories with mitigations, not a doom mood. If the run reads as "everything is risky," it failed.
• Likelihood and severity are different axes. The most likely failure and the most dangerous failure are usually not the same one. Surface both — that distinction is often the insight.

Customization

Before executing, check for user customizations at ~/.claude/PAI/USER/SKILLCUSTOMIZATIONS/Premortem/. If PREFERENCES.md exists, load and apply it (e.g. preferred default horizon, report theme, number of failure agents). These override defaults. If the directory does not exist, proceed with skill defaults. Do not put private/identity content in this skill body — it belongs in SKILLCUSTOMIZATIONS.

🚨 Voice Notification (run on invocation)

curl -s -X POST http://localhost:31337/notify \
  -H "Content-Type: application/json" \
  -d '{"message": "Running the WORKFLOWNAME workflow in the Premortem skill to ACTION"}' \
  > /dev/null 2>&1 &

Then output: Running the **WorkflowName** workflow in the **Premortem** skill to ACTION...

Examples

Example 1: Full premortem on a launch

User: "Premortem our paid-newsletter launch next month"
→ RunPremortem: gather context (what/who/success) → frame "it's 6 months out, the launch failed"
→ generate plan-specific causes → fan out 1 agent per cause (independent) → synthesize
   most-likely + most-dangerous + hidden assumption + revised plan + checklist
→ write transcript .md, optionally GenerateReport.ts --html → 3-sentence chat summary

Example 2: Quick solo gut-check

User: "quick premortem on accepting this contractor role"
→ QuickPremortem: single-pass, no agents → past-tense framing → 5-8 specific causes with
   likelihood/severity, hidden assumption, top mitigations → short markdown, no HTML

Example 3: Disambiguation from RedTeam

User: "poke holes in my argument that we should go remote-first"
→ This is attacking an ARGUMENT, not a plan-with-stakes → suggest RedTeam instead, or
   reframe: "if you want to premortem the remote-first *rollout plan*, I can do that."

Execution Log

After completing any workflow, append a single JSONL entry:

echo '{"ts":"'$(date -u +%Y-%m-%dT%H:%M:%SZ)'","skill":"Premortem","workflow":"WORKFLOW_USED","input":"8_WORD_SUMMARY","status":"ok|error","duration_s":SECONDS}' >> ~/.claude/PAI/MEMORY/SKILLS/execution.jsonl