From arn-spark
This skill should be used when the user says "pre-mortem", "premortem", "risk analysis", "stress premortem", "failure analysis", "what could go wrong", "pre mortem", "investigate failure", "failure modes", or wants to stress-test a product concept by applying Gary Klein's pre-mortem methodology to identify hypothetical failure root causes, early warning signals, and mitigation strategies. Produces a pre-mortem report with 3 root causes across distinct failure dimensions and recommended concept updates.
npx claudepluginhub appsvortex/arness --plugin arn-sparkThis skill uses the workspace's default tool permissions.
Searches, retrieves, and installs Agent Skills from prompts.chat registry using MCP tools like search_skills and get_skill. Activates for finding skills, browsing catalogs, or extending Claude.
Searches prompts.chat for AI prompt templates by keyword or category, retrieves by ID with variable handling, and improves prompts via AI. Use for discovering or enhancing prompts.
Delivers idiomatic Kotlin patterns for null safety, immutability, sealed classes, coroutines, Flows, extensions, DSL builders, and Gradle DSL. Use when writing, reviewing, refactoring, or designing Kotlin code.
Stress-test a product concept using Gary Klein's pre-mortem methodology. Instead of asking "what could go wrong?" (which invites optimism bias), the pre-mortem declares that the product has already launched and failed, then investigates why.
The process works like this:
This technique surfaces failure modes that optimism obscures. The product concept is read but never modified -- all recommendations are captured in the pre-mortem report for later review.
CLAUDE.md and check for a ## Arness section## Arness section exists or Arness Spark fields are missing, inform the user: "Arness Spark is not configured for this project yet. Run /arn-brainstorming to get started — it will set everything up automatically." Do not proceed without it.mkdir -p <reports-dir>/stress-tests/| Artifact | Status | Location | Fallback |
|---|---|---|---|
| Product concept | REQUIRED | <vision-dir>/product-concept.md | Cannot proceed without it -- suggest running /arn-spark-discover |
| Product pillars | ENRICHES | Product Pillars section of product concept | Investigation proceeds but pillar-as-evidence analysis is less targeted |
| Competitive landscape | ENRICHES | Competitive Landscape section of product concept | Root Cause C (market misread) is less grounded in competitive dynamics |
| Target personas | ENRICHES | Target Personas section of product concept | Root Cause A and C are less grounded in persona-specific failure scenarios |
Product concept fallback:
If no product concept exists:
Ask (using AskUserQuestion): "No product concept found. The pre-mortem needs a product concept to investigate. How would you like to proceed?"
/arn-spark-discover to create a product concept firstIf the user chooses option 2, collect a product description and proceed with a reduced-fidelity investigation (note in the report that the investigation was based on a verbal description rather than a full product concept).
Load the pre-mortem protocol and report template:
Read
${CLAUDE_PLUGIN_ROOT}/skills/arn-spark-stress-premortem/references/premortem-protocol.mdRead${CLAUDE_PLUGIN_ROOT}/skills/arn-spark-stress-premortem/references/premortem-report-template.md
Read the product concept from <vision-dir>/product-concept.md. Extract:
Invoke arn-spark-forensic-investigator with:
--- PRODUCT CONCEPT --- [full product concept document] --- END PRODUCT CONCEPT ---
--- PRODUCT PILLARS --- [product pillars section -- these are forensic evidence, not goals to protect] --- END PRODUCT PILLARS ---
--- COMPETITIVE LANDSCAPE --- [competitive landscape section, or "Not available" if absent] --- END COMPETITIVE LANDSCAPE ---
--- TARGET PERSONAS --- [target personas section from the product concept, or "Not available" if absent] --- END TARGET PERSONAS ---
--- INVESTIGATION TASK --- Standard investigation: Generate 3 root causes across distinct failure dimensions:
For each root cause: failure narrative, causal chain (4 links), early warning signals (3), mitigation strategies (3), likelihood assessment, severity assessment.
Include a Recommended Concept Updates table and Unresolved Questions section. --- END INVESTIGATION TASK ---
Review the forensic investigator's output for quality:
If quality is insufficient: Retry with an explicit adversarial instruction:
"The investigation was too soft. Requirements:
If the retry also fails quality checks, proceed with the best available output and note the quality gap in the report.
Review the investigator's Recommended Concept Updates table. Ensure:
# | Section | Current State | Recommended Change | Type | RationaleIf the investigator's recommendations are incomplete, supplement from the mitigation strategies.
Using the pre-mortem report template:
<reports-dir>/stress-tests/premortem-report.mdPresent a summary to the user:
"Pre-mortem investigation complete. Report saved to [path].
Failure premise: [Product name] launched and was shut down 12 months later.
Root causes identified:
Risk priority: [N] root causes require immediate attention, [N] require mitigation Recommended concept updates: [N] recommendations ([X] Add, [Y] Modify, [Z] Remove) Unresolved questions: [N]
This report will be used by /arn-spark-concept-review to propose changes to the product concept."
| Situation | Agent | Mode/Context |
|---|---|---|
| Standard pre-mortem investigation | arn-spark-forensic-investigator | Full product concept with pillars and competitive landscape |
| Targeted deep-dive (future) | arn-spark-forensic-investigator | Specific failure scenario for extended analysis |
Forensic investigator produces soft/hedged failures: Retry with explicit adversarial instruction emphasizing that failures must be specific, vivid, and grounded in product concept details. Include: "Generic failures like 'users did not find it useful' are worthless -- explain exactly why and how."
Forensic investigator produces fewer than 3 root causes: Retry specifying which failure dimension is missing and providing additional context for that dimension. If retry still produces fewer than 3, proceed with available output and note the gap.
Forensic investigator produces overlapping root causes: Retry specifying that each root cause must have a distinct causal mechanism. If two root causes share the same first link in the causal chain, they are one root cause.
Agent invocation fails entirely: Retry once with a simplified prompt. If retry fails:
Ask (using AskUserQuestion): "Agent invocation failed. How would you like to proceed?"
premortem-report.md already exists, it is overwritten. Git provides history.