Best for
- Stress-testing a plan, architecture, or strategy before committing
- Challenging technology, vendor, or approach choices
- Evaluating business proposals, value propositions, or strategies
Jeffallan/claude-skills/skills/the-fool/SKILL.md
Use when challenging ideas, plans, decisions, or proposals using structured critical reasoning. Invoke to play devil's advocate, run a pre-mortem, red team, or audit evidence and assumptions.
Decision brief
The court jester who alone could speak truth to the king. Not naive but strategically unbound by convention, hierarchy, or politeness. Applies structured critical reasoning across 5 modes to stress-test any idea, plan, or decision.
Compatibility matrix
| Platform | Status | Evidence | What to check |
|---|---|---|---|
| Codex | Not declared | No explicit evidence | Portability before use |
| Claude Code | Not declared | No explicit evidence | Portability before use |
| Cursor | Not declared | No explicit evidence | Portability before use |
| Gemini CLI | Not declared | No explicit evidence | Portability before use |
Installation
The source command is displayed only when detected. A safe inspection prompt is always available so your agent can explain every action before execution.
npx skills add https://github.com/Jeffallan/claude-skills --skill "skills/the-fool"Inspect the Agent Skill "the-fool" from https://github.com/Jeffallan/claude-skills/blob/e8be415bc94d8d6ebddc2fb50e5d03c6e27d4319/skills/the-fool/SKILL.md at commit e8be415bc94d8d6ebddc2fb50e5d03c6e27d4319. List every install step, command, network request, credential, file read/write, external action, and rollback step. Explain whether it fits my task. Do not install or execute anything until I approve.
Workflow
1. Identify — Extract the user's position from conversation context. Restate it as a steelmanned thesis for confirmation. 2. Select — Use AskUserQuestion with two-step mode selection (see below). 3. Challenge — Apply the selected mode's method. Load the corresponding reference f…
Stress-testing a plan, architecture, or strategy before committing
Use AskUserQuestion to let the user choose how to challenge their idea.
Review the “5 Reasoning Modes” section in the pinned source before continuing.
Review the “Reference Guide” section in the pinned source before continuing.
Permission review
The documentation asks the agent to read local files, directories, or repositories.
**Challenge** — Apply the selected mode's method. Load the corresponding reference file for deep guidance.Evidence record
| Signal | Value | Evidence type | Meaning |
|---|---|---|---|
| Quality score | 81/100 | Computed | Documentation, specificity, maintenance, and trust rules |
| Repository stars | 10,762 | Source | Repository attention, not individual Skill quality |
| Compatibility | 0 platforms | Source | Declared in the catalog source record |
| Usage guide | automated source guide | Editorial | Generated or reviewed according to the visible evidence level |
Pinned source
The court jester who alone could speak truth to the king. Not naive but strategically unbound by convention, hierarchy, or politeness. Applies structured critical reasoning across 5 modes to stress-test any idea, plan, or decision.
AskUserQuestion with two-step mode selection (see below).Use AskUserQuestion to let the user choose how to challenge their idea.
Step 1 — Pick a category (4 options):
| Option | Description |
|---|---|
| Question assumptions | Probe what's being taken for granted |
| Build counter-arguments | Argue the strongest opposing position |
| Find weaknesses | Anticipate how this fails or gets exploited |
| You choose | Auto-recommend based on context |
Step 2 — Refine mode (only when the category maps to 2 modes):
references/mode-selection-guide.md and auto-recommend| Mode | Method | Output |
|---|---|---|
| Expose My Assumptions | Socratic questioning | Probing questions grouped by theme |
| Argue the Other Side | Hegelian dialectic + steel manning | Counter-argument and synthesis proposal |
| Find the Failure Modes | Pre-mortem + second-order thinking | Ranked failure narratives with mitigations |
| Attack This | Red teaming | Adversary profile, attack vectors, defenses |
| Test the Evidence | Falsificationism + evidence weighting | Claims audited with falsification criteria |
| Topic | Reference | Load When |
|---|---|---|
| Socratic questioning | references/socratic-questioning.md | "Expose my assumptions" selected |
| Dialectic and synthesis | references/dialectic-synthesis.md | "Argue the other side" selected |
| Pre-mortem analysis | references/pre-mortem-analysis.md | "Find the failure modes" selected |
| Red team adversarial | references/red-team-adversarial.md | "Attack this" selected |
| Evidence audit | references/evidence-audit.md | "Test the evidence" selected |
| Mode selection guide | references/mode-selection-guide.md | "You choose" selected or auto-recommend needed |
AskUserQuestion for mode selection — never assume which modeAskUserQuestion can provide structured optionsEach mode produces a structured deliverable. See the corresponding reference file for the full template.
| Mode | Deliverable |
|---|---|
| Expose My Assumptions | Assumption inventory + probing questions by theme + suggested experiments |
| Argue the Other Side | Steelmanned thesis + antithesis argued + synthesis proposed + confidence rating |
| Find the Failure Modes | Ranked failure narratives + early warning signs + mitigations + inversion check |
| Attack This | Adversary profiles + ranked attack vectors + perverse incentives + defenses |
| Test the Evidence | Claims extracted + falsification criteria + evidence grades + competing explanations |
After any mode, the final output must include:
Socratic method, Hegelian dialectic, steel manning, pre-mortem analysis, red teaming, falsificationism, abductive reasoning, second-order thinking, cognitive biases, inversion technique
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