Pre Mortem

Pre-Mortem Skill (pre-mortem)

Stress-test plans and design documents using Gary Klein's "prospective hindsight" technique. Time-travel 6 months into the future to a state where your plan has failed completely, reverse-engineer why it failed, spawn parallel investigators to analyze each failure, and synthesize early warning signs, a revised plan, and a pre-launch checklist.

Overview

A pre-mortem is one of the most powerful risk mitigation tools available. It operates under a simple cognitive shift: instead of asking "what might go wrong?", you state "it is 6 months in the future, and this project has completely failed. Let's write the history of that failure."

This cognitive shift bypasses groupthink, unlocks creative skepticism, and exposes deep, unexamined assumptions before a single line of code is written or deployed.

Steps

Step 1: gather_context

The agent scans the active conversation and the local workspace (including design documents, plans, and configuration files) to build a comprehensive understanding of the proposed plan:

• Determine the scope, target audience, execution steps, technology stack, and success criteria.
• If the current context is insufficient to conduct a rigorous pre-mortem, the agent must ask highly focused, sequential questions (one at a time) to extract the necessary plan details. No pre-existing brief is required.

Step 2: failure_generation [depends_on: gather_context]

The agent shifts the cognitive frame: "It is 6 months in the future. The plan has failed catastrophically. It is a smoking ruin."

• Generate a list of realistic, distinct failure modes (typically 4 to 9 depending on the complexity of the plan).
• Each failure mode must be genuine, specific to the plan, and cover technical, operational, organizational, or dependency failures. Avoid generic or superficial answers.

Step 3: parallel_investigators [depends_on: failure_generation]

For each generated failure mode, the agent spawns (or simulates the parallel execution of) independent specialized sub-agent investigators:

• Each investigator goes deep into its assigned failure mode.
• Each investigator produces:
  1. A detailed case study of how this specific failure played out step-by-step.
  2. The single biggest hidden assumption that enabled this failure.
  3. Early warning signs (telemetry, metrics, behavioral indicators) that would be visible weeks before the crash.

Step 4: synthesis [depends_on: parallel_investigators]

The agent compiles and synthesizes the findings of the parallel investigators into a structured strategic output:

• Most Likely Failure: The failure mode with the highest probability that requires immediate, proactive changes.
• Most Dangerous Failure: The high-impact, existential failure mode that is worth purchasing insurance against, even if less likely.
• Root Assumption: The single most significant hidden assumption underpinning the original plan.
• Revised Plan: An actionable, updated version of the plan with specific, concrete changes mapped directly to the discovered failure modes.
• Pre-Launch Checklist: A list of 3-5 concrete, testable conditions that must be verified before shipping the plan.

Step 5: visual_reporting [depends_on: synthesis]

The agent outputs the final pre-mortem results in two high-fidelity formats:

• Visual HTML Report: A premium, beautifully styled HTML document (rendered using premium CSS, curated dark palettes, elegant gradients, and clear typography) containing the synthesis and a summary of the investigator findings.
• Markdown Transcript: A clean, comprehensive markdown transcript detailing the full step-by-step reasoning of each parallel investigator.

Visual Report Aesthetics

To wow the user and create a premium product feel, the Visual HTML Report should adhere to the following design aesthetics:

• Color Palette: Dark mode base (#0f172a, #1e293b) with vibrant, high-contrast semantic accents (e.g., deep ruby #ef4444 for failures, glowing emerald #10b981 for checklist items, and warm amber #f59e0b for assumptions).
• Typography: Modern typography utilizing premium Google Fonts (e.g., Outfit or Inter).
• Interactive Elements: CSS-based accordion drawers for case studies, interactive checkboxes for the pre-launch checklist, and sleek, glassmorphic container cards with subtle hover transitions.
• Structure:
  1. Header with plan name, version, and the simulated future failure date.
  2. A "Risk Profile Matrix" displaying the Most Likely vs. Most Dangerous failures.
  3. "The Investigators' Files" containing the detailed case studies and early warning signs.
  4. The "Revised Plan" showing side-by-side or clear diffs of modifications.
  5. The interactive "Pre-Launch Checklist".

Best Practices

• Avoid Complacency: Do not list trivial or obvious failure modes (e.g., "the server ran out of disk space" unless it is highly probable). Push for nuanced architectural or social failure paths.
• Prospective Hindsight Frame: Ensure the language in Step 2 and Step 3 is strictly written in the past tense as if the failure has already occurred.
• Actionability: A pre-mortem is only valuable if it changes the current plan. The "Revised Plan" must have clear, tangible differences from the original.