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Stress Test

/em:stress-test — Business assumption stress testing. Use before betting on a plan whose core assumptions are unvalidated — e.g. stress-testing 'enterprise buyers will tolerate a 6-month pilot' or a hockey-stick revenue model.

testing
By alirezarezvani
21k2.8kUpdated 3 days agoPythonMIT

Skill Content

# /em:stress-test — Business Assumption Stress Testing

**Command:** `/em:stress-test <assumption>`

Take any business assumption and break it before the market does. Revenue projections. Market size. Competitive moat. Hiring velocity. Customer retention.

---

## Why Most Assumptions Are Wrong

Founders are optimists by nature. That's a feature — you need optimism to start something from nothing. But it becomes a liability when assumptions in business models get inflated by the same optimism that got you started.

**The most dangerous assumptions are the ones everyone agrees on.**

When the whole team believes the $50M market is real, when every investor call goes well so you assume the round will close, when your model shows $2M ARR by December and nobody questions it — that's when you're most exposed.

Stress testing isn't pessimism. It's calibration.

---

## The Stress-Test Methodology

### Step 1: Isolate the Assumption

State it explicitly. Not "our market is large" but "the total addressable market for B2B spend management software in German SMEs is €2.3B."

The more specific the assumption, the more testable it is. Vague assumptions are unfalsifiable — and therefore useless.

**Common assumption types:**
- **Market size** — TAM, SAM, SOM; growth rate; customer segments
- **Customer behavior** — willingness to pay, churn, expansion, referrals
- **Revenue model** — conversion rates, deal size, sales cycle, CAC
- **Competitive position** — moat durability, competitor response speed, switching cost
- **Execution** — team velocity, hire timeline, product timeline, operational scaling
- **Macro** — regulatory environment, economic conditions, technology availability

### Step 2: Find the Counter-Evidence

For every assumption, actively search for evidence that it's wrong.

Ask:
- Who has tried this and failed?
- What data contradicts this assumption?
- What does the bear case look like?
- If a smart skeptic was looking at this, what would they point to?
- What's the base rate for assumptions like this?

**Sources of counter-evidence:**
- Comparable companies that failed in adjacent markets
- Customer churn data from similar businesses
- Historical accuracy of similar forecasts
- Industry reports with conflicting data
- What competitors who tried this found

The goal isn't to find a reason to stop — it's to surface what you don't know.

### Step 3: Model the Downside

Most plans model the base case and the upside. Stress testing means modeling the downside explicitly.

**For quantitative assumptions (revenue, growth, conversion):**

| Scenario | Assumption Value | Probability | Impact |
|----------|-----------------|-------------|--------|
| Base case | [Original value] | ? | |
| Bear case | -30% | ? | |
| Stress case | -50% | ? | |
| Catastrophic | -80% | ? | |

Key question at each level: **Does the business survive? Does the plan make sense?**

**For qualitative assumptions (moat, product-market fit, team capability):**

- What's the earliest signal this assumption is wrong?
- How long would it take you to notice?
- What happens between when it breaks and when you detect it?

### Step 4: Calculate Sensitivity

Some assumptions matter more than others. Sensitivity analysis answers: **if this one assumption changes, how much does the outcome change?**

Example: 
- If CAC doubles, how does that change runway?
- If churn goes from 5% to 10%, how does that change NRR in 24 months?
- If the deal cycle is 6 months instead of 3, how does that affect Q3 revenue?

High sensitivity = the assumption is a key lever. Wrong = big problem.

### Step 5: Propose the Hedge

For every high-risk assumption, there should be a hedge:

- **Validation hedge** — test it before betting on it (pilot, customer conversation, small experiment)
- **Contingency hedge** — if it's wrong, what's plan B?
- **Early warning hedge** — what's the leading indicator that would tell you it's breaking before it's too late to act?

---

## Stress Test Patterns by Assumption Type

### Revenue Projections

**Common failures:**
- Bottom-up model assumes 100% of pipeline converts
- Doesn't account for deal slippage, churn, seasonality
- New channel assumed to work before tested at scale

**Stress questions:**
- What's your actual historical win rate on pipeline?
- If your top 3 deals slip to next quarter, what happens to the number?
- What's the model look like if your new sales rep takes 4 months to ramp, not 2?
- If expansion revenue doesn't materialize, what's the growth rate?

**Test:** Build the revenue model from historical win rates, not hoped-for ones.

### Market Size

**Common failures:**
- TAM calculated top-down from industry reports without bottoms-up validation
- Conflating total market with serviceable market
- Assuming 100% of SAM is reachable

**Stress questions:**
- How many companies in your ICP actually exist and can you name them?
- What's your serviceable obtainable market in year 1-3?
- What percentage of your ICP is currently spending on any solution to this problem?
- What does "winning" look like and what market share does that require?

**Test:** Build a list of target accounts. Count them. Multiply by ACV. That's your SAM.

### Competitive Moat

**Common failures:**
- Moat is technology advantage that can be built in 6 months
- Network effects that haven't yet materialized
- Data advantage that requires scale you don't have

**Stress questions:**
- If a well-funded competitor copied your best feature in 90 days, what do customers do?
- What's your retention rate among customers who have tried alternatives?
- Is the moat real today or theoretical at scale?
- What would it cost a competitor to reach feature parity?

**Test:** Ask churned customers why they left and whether a competitor could have kept them.

### Hiring Plan

**Common failures:**
- Time-to-hire assumes standard recruiting cycle, not current market
- Ramp time not modeled (3-6 months before full productivity)
- Key hire dependency: plan only works if specific person is hired

**Stress questions:**
- What happens if the VP Sales hire takes 5 months, not 2?
- What does execution look like if you only hire 70% of planned headcount?
- Which single person, if they left tomorrow, would most damage the plan?
- Is the plan achievable with current team if hiring freezes?

**Test:** Model the plan with 0 net new hires. What still works?

### Competitive Response

**Common failures:**
- Assumes incumbents won't respond (they will if you're winning)
- Underestimates speed of response
- Doesn't model resource asymmetry

**Stress questions:**
- If the market leader copies your product in 6 months, how does pricing change?
- What's your response if a competitor raises $30M to attack your space?
- Which of your customers have vendor relationships with your competitors?

---

## The Stress Test Output

```
ASSUMPTION: [Exact statement]
SOURCE: [Where this came from — model, investor pitch, team gut feel]

COUNTER-EVIDENCE
• [Specific evidence that challenges this assumption]
• [Comparable failure case]
• [Data point that contradicts the assumption]

DOWNSIDE MODEL
• Bear case (-30%): [Impact on plan]
• Stress case (-50%): [Impact on plan]
• Catastrophic (-80%): [Impact on plan — does the business survive?]

SENSITIVITY
This assumption has [HIGH / MEDIUM / LOW] sensitivity.
A 10% change → [X] change in outcome.

HEDGE
• Validation: [How to test this before betting on it]
• Contingency: [Plan B if it's wrong]
• Early warning: [Leading indicator to watch — and at what threshold to act]
```

How to use

  1. Copy the skill content above
  2. Create a .claude/skills directory in your project
  3. Save as .claude/skills/claude-skills-stress-test.md
  4. Use /claude-skills-stress-test in Claude Code to invoke this skill

Claude Code Skills & Plugins — Agent Skills for Every Coding Tool

355 production-ready Claude Code skills, plugins, and agent skills for 13 AI coding tools.

The most comprehensive open-source library of Claude Code skills and agent plugins — also works with OpenAI Codex, Gemini CLI, Cursor, and 9 more coding agents. Reusable expertise packages covering engineering, DevOps, marketing (incl. AEO — Answer Engine Optimization for LLM citation), security (PreToolUse hooks), compliance, C-level advisory (incl. founder-mode CFO/CMO/CRO/CPO/COO/CHRO/CISO/GC/CDO/CAIO/CCO/VPE personas + 21 /cs:* slash commands), productivity (capture/email/reflect), an academic research stack (litreview/grants/dossier/patent/syllabus/pulse/notebooklm/deep-research + hybrid router), and enterprise Research Operations (clinical-research/research-finance/market-research/product-research, v2.9.0).

Works with: Claude Code · OpenAI Codex · Gemini CLI · OpenClaw · Hermes Agent1 · Mistral Vibe2 · Cursor · Aider · Windsurf · Kilo Code · OpenCode · Augment · Antigravity

License: MIT Skills Agents Personas Commands Stars SkillCheck Validated

5,200+ GitHub stars — the most comprehensive open-source Claude Code skills & agent plugins library.


What Are Claude Code Skills & Agent Plugins?

Claude Code skills (also called agent skills or coding agent plugins) are modular instruction packages that give AI coding agents domain expertise they don't have out of the box. Each skill includes:

  • SKILL.md — structured instructions, workflows, and decision frameworks
  • Python tools — 602 CLI scripts (all stdlib-only, zero pip installs)
  • Reference docs — 711 templates, checklists, and domain-specific knowledge files

One repo, thirteen platforms. Works natively as Claude Code plugins, Codex agent skills, Gemini CLI skills, Hermes Agent skills, Mistral Vibe skills, and converts to more tools via scripts/convert.sh. All 602 Python tools run anywhere Python runs.

Skills vs Agents vs Personas

SkillsAgentsPersonas
PurposeHow to execute a taskWhat task to doWho is thinking
ScopeSingle domainSingle domainCross-domain
VoiceNeutralProfessionalPersonality-driven
Example"Follow these steps for SEO""Run a security audit""Think like a startup CTO"

All three work together. See Orchestration for how to combine them.


Quick Install

Gemini CLI (New)

# Clone the repository
git clone https://github.com/alirezarezvani/claude-skills.git
cd claude-skills

# Run the setup script
./scripts/gemini-install.sh

# Start using skills
> activate_skill(name="senior-architect")

Claude Code (Recommended)

# Add the marketplace
/plugin marketplace add alirezarezvani/claude-skills

# Install by domain
/plugin install engineering-skills@claude-code-skills          # 24 core engineering
/plugin install engineering-advanced-skills@claude-code-skills  # 25 POWERFUL-tier
/plugin install product-skills@claude-code-skills               # 12 product skills
/plugin install marketing-skills@claude-code-skills             # 43 marketing skills
/plugin install ra-qm-skills@claude-code-skills                 # 12 regulatory/quality
/plugin install pm-skills@claude-code-skills                    # 6 project management
/plugin install c-level-skills@claude-code-skills               # 28 C-level advisory (full C-suite)
/plugin install business-growth-skills@claude-code-skills       # 4 business & growth
/plugin install finance-skills@claude-code-skills               # 2 finance (analyst + SaaS metrics)

# Or install individual skills
/plugin install skill-security-auditor@claude-code-skills       # Security scanner
/plugin install playwright-pro@claude-code-skills                  # Playwright testing toolkit
/plugin install self-improving-agent@claude-code-skills         # Auto-memory curation
/plugin install content-creator@claude-code-skills              # Single skill

OpenAI Codex

npx agent-skills-cli add alirezarezvani/claude-skills --agent codex
# Or: git clone + ./scripts/codex-install.sh

OpenClaw

bash <(curl -s https://raw.githubusercontent.com/alirezarezvani/claude-skills/main/scripts/openclaw-install.sh)

Manual Installation

git clone https://github.com/alirezarezvani/claude-skills.git
# Copy any skill folder to ~/.claude/skills/ (Claude Code) or ~/.codex/skills/ (Codex)

Multi-Tool Support (New)

Convert all 345 skills to 9 AI coding tools with a single script:

ToolFormatInstall
Cursor.mdc rules./scripts/install.sh --tool cursor --target .
AiderCONVENTIONS.md./scripts/install.sh --tool aider --target .
Kilo Code.kilocode/rules/./scripts/install.sh --tool kilocode --target .
Windsurf.windsurf/skills/./scripts/install.sh --tool windsurf --target .
OpenCode.opencode/skills/./scripts/install.sh --tool opencode --target .
Augment.augment/rules/./scripts/install.sh --tool augment --target .
Antigravity~/.gemini/antigravity/skills/./scripts/install.sh --tool antigravity
Hermes Agent~/.hermes/skills/python scripts/sync-hermes-skills.py --verbose
Mistral Vibe~/.vibe/skills/./scripts/vibe-install.sh

How it works:

# 1. Convert all skills to all tools (takes ~15 seconds)
./scripts/convert.sh --tool all

# 2. Install into your project (with confirmation)
./scripts/install.sh --tool cursor --target /path/to/project

# Or use --force to skip confirmation:
./scripts/install.sh --tool aider --target . --force

# 3. Verify
find .cursor/rules -name "*.mdc" | wc -l  # Should show 346

Each tool gets:

  • ✅ All 345 skills converted to native format
  • ✅ Per-tool README with install/verify/update steps
  • ✅ Support for scripts, references, templates where applicable
  • ✅ Zero manual conversion work

Run ./scripts/convert.sh --tool all to generate tool-specific outputs locally.


Skills Overview

355 skills across 18 domains:

DomainSkillsHighlightsDetails
🔧 Engineering — Core52Architecture, frontend, backend, fullstack, QA, DevOps, SecOps, AI/ML, data, Playwright Pro (test gen, flaky fix, migrations), self-improving agent (auto-memory curation), security suite, a11y audit, named-persona-adversarial-review (review via named engineering philosophies)engineering-team/
⚡ Engineering — POWERFUL81Agent designer, RAG architect, database designer, CI/CD builder, security auditor, MCP builder, AgentHub, Helm charts, Terraform, self-eval, llm-wiki, tc-tracker, autoresearch-agent, reliability portfolio (feature-flags-architect, kubernetes-operator, chaos-engineering, slo-architect), ship-gate, security-guidance PreToolUse hook, Matt Pocock skills (write-a-skill, caveman, grill-me, handoff, grill-with-docs), zero-hallucination-coder (Discuss→Map→Decompose→Execute→Verify), agent-harness (goal→plan→execute→verify→close loops over any domain)engineering/
🎯 Product17Product manager, agile PO, strategist, UX researcher, UI design, landing pages, SaaS scaffolder, analytics, experiment designer, discovery, roadmap communicator, code-to-prd, apple-hig-expertproduct-team/
📣 Marketing488 pods: Content, SEO + AEO (aeo — E-E-A-T audit, citation tracking across 5 LLMs) + local (local-seo-manager — GBP/NAP/Map-Pack), CRO, Channels, Growth, Intelligence, Sales + context foundation + orchestration routermarketing-skill/
🚀 Productivity7capture (brain-dump-to-action), email pair (inbox-setup + inbox-triage), reflect (journal), handoff (Matt Pocock-inspired), andreessen (market-first decision mode), roast (5-angle idea panel → GO/RESHAPE/KILL)productivity/
🎨 Marketing (top-level)1landing — single-file HTML landing-page generator (4 design styles, GSAP patterns, brand palette validator)marketing/
🔬 Research (academic)9research orchestrator (hybrid router + fallback) + 8 specialists: pulse, litreview, grants (NIH), dossier, patent, syllabus, notebooklm, deep-research (rigor-first meta-research)research/
🧪 Research Operations ✨v2.9.05Enterprise/cross-functional research: orchestrator + clinical-research (study design), research-finance (R&D program finance), market-research (sizing/survey/segmentation), product-research (user research) — each with onboarding + customization + opt-in autoresearch bridgeresearch-ops/
📋 Project Management9Senior PM, scrum master, Jira, Confluence, Atlassian admin, templates + bundled Atlassian Remote MCPproject-management/
🏥 Regulatory & QM19ISO 13505, MDR 2017/745, FDA, ISO 27001, GDPR, SOC 2, CAPA, risk management, agent-decision-receipts (PQ-signed action receipts)ra-qm-team/
🛡️ Compliance OS9Compliance operating system — controls, evidence, audit-readiness workflowscompliance-os/
💼 C-Level Advisory68Full C-suite (CEO/CTO/CFO/CMO/CRO/CPO/COO/CHRO/CISO/GC/CDO/CAIO/CCO/VPE) + founder-mode agents + orchestration + board meetings + culture & collaborationc-level-advisor/
📈 Business & Growth5Customer success, sales engineer, revenue ops, contracts & proposals, BizDev toolkitbusiness-growth/
🏭 Business Operations7Orchestrator + process-mapper, vendor-management, capacity-planner, internal-comms, knowledge-ops, procurement-optimizerbusiness-operations/
🤝 Commercial8Orchestrator + pricing-strategist, deal-desk, partnerships-architect, channel-economics, commercial-policy, rfp-responder, commercial-forecastercommercial/
💰 Finance4Financial analyst (DCF, budgeting, forecasting), SaaS metrics coach, business investment advisorfinance/
🔄 Loop Library1loop-library — discover, find, audit/repair, adapt, and design bounded AI-agent loops; reads the live catalog from signals.forwardfuture.ai at runtime (vendored verbatim from [Forward-Future/loop-library](https://github.com/Forward-Future/loop-libr

Footnotes

  1. Hermes Agent is BYO-sync tier: the repo ships a pre-generated .hermes/skills/claude-skills/ tree, but you run python scripts/sync-hermes-skills.py once locally to install into ~/.hermes/skills/. Uses the same agentskills.io SKILL.md standard — no format conversion.

  2. Mistral Vibe is also BYO-sync tier: the repo ships a pre-generated .vibe/skills/claude-skills/ tree, run ./scripts/vibe-install.sh once locally to install into ~/.vibe/skills/. Same agentskills.io SKILL.md standard — no format conversion. Docs: https://docs.mistral.ai/mistral-vibe/agents-skills.

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