Assumption Buster
Aggressively identify, challenge, and attempt to disprove assumptions through systematic counterexample generation, edge case exploration, and adversarial thinking to reveal hidden weaknesses and false beliefs.
When to use me
Use this skill when:
- Critical decisions rely on untested assumptions
- Systems have high failure costs (safety, financial, reputation)
- You suspect team is suffering from confirmation bias
- Preparing for adversarial environments (security, competition, regulation)
- Testing resilience of core system beliefs
- Validating fundamental premises before major investments
- Challenging "industry best practices" that may not apply
- Stress-testing architectural decisions
- Preparing for audits, penetration tests, or regulatory reviews
What I do
1. Assumption Aggression
- Actively seek to disprove rather than just test assumptions
- Generate counterexamples that break the assumption
- Find edge cases where assumption fails catastrophically
- Identify contradiction patterns in evidence
- Pressure-test boundary conditions until they break
2. Disproof Methodology
- Attempt falsification using Popperian scientific method
- Search for black swans - rare but catastrophic counterexamples
- Construct stress scenarios that maximize assumption failure
- Apply Murphy's Law - "anything that can go wrong, will"
- Explore combinatorial explosions of failure modes
3. Adversarial Testing
- Think like an attacker trying to break the system
- Adopt competitor mindset looking for weaknesses to exploit
- Simulate hostile environments (limited resources, malicious actors)
- Test under extreme conditions beyond design specifications
- Provoke failure cascades and ripple effects
4. Cognitive Bias Countermeasures
- Target confirmation bias by seeking disconfirming evidence
- Challenge availability heuristic by looking for rare cases
- Counter anchoring effect by exploring extreme values
- Overcome overconfidence with rigorous stress testing
- Break groupthink by introducing dissenting perspectives
Assumption Busting Techniques
For Technical Assumptions:
- Load to failure: "What load breaks this assumption?"
- Resource starvation: "What happens with minimal resources?"
- Dependency failure: "What if every dependency fails simultaneously?"
- Version hell: "What if all versions are mismatched?"
- Data corruption: "What if data is intentionally malformed?"
For Business Assumptions:
- Market reversal: "What if customer preferences change overnight?"
- Competitor innovation: "What if a competitor solves this better/cheaper?"
- Regulatory shock: "What if regulations completely change?"
- Economic collapse: "What if funding disappears?"
- Team dissolution: "What if key people leave?"
For Process Assumptions:
- Communication breakdown: "What if all communication fails?"
- Tool failure: "What if primary tools become unavailable?"
- Knowledge loss: "What if institutional knowledge disappears?"
- Timeline compression: "What if deadlines move up 90%?"
- Quality erosion: "What if quality standards steadily decline?"
Examples
# Aggressively test a technical assumption
npm run assumption-buster:disprove -- --assumption "database-always-available" --method "chaos-engineering"
# Find counterexamples for a business assumption
npm run assumption-buster:counterexamples -- --assumption "users-prefer-mobile" --data "analytics-export.csv"
# Stress-test architectural decisions
npm run assumption-buster:stress-test -- --architecture "event-driven" --scenario "complete-network-partition"
# Generate failure scenarios for a process
npm run assumption-buster:failure-scenarios -- --process "ci-cd-pipeline" --intensity extreme
# Comprehensive assumption busting
npm run assumption-buster:all -- --criticality high --thoroughness maximum
Output format
Assumption Busting Report
──────────────────────────────
Target: Payment Processing System
Assumptions Targeted: 14
Busting Duration: 2 hours
Busting Intensity: Aggressive
Assumption Busting Results:
1. Assumption: "Payment gateway responses always within 2 seconds"
Status: ❌ BUSTED (Catastrophically)
Counterexamples Found:
- Network partition causes indefinite hangs (no timeout)
- Gateway DDoS attack results in 30+ second responses
- SSL certificate expiration causes silent failures
- DNS poisoning redirects to malicious endpoints
- Gateway vendor bankruptcy (no responses at all)
Stress Test Results:
- Under simulated attack: 85% of requests exceed 2 seconds
- Failure cascade: timeouts cause thread pool exhaustion
- Worst-case latency: 47 seconds (complete system stall)
Impact if Believed:
- Payment system becomes unresponsive during attacks
- Financial losses from failed transactions
- Customer trust destroyed
- Recovery requires complete system restart
Recommendation:
Implement circuit breakers, aggressive timeouts, fallback providers
2. Assumption: "Users always complete checkout in single session"
Status: ⚠️ PARTIALLY BUSTED (Significant weaknesses)
Counterexamples Found:
- Mobile network drops during payment (common)
- Browser crashes after cart creation (frequent)
- Users comparison shop across tabs (standard behavior)
- Payment requires external verification (bank 2FA)
- Users interrupted by real-world events (constant)
Stress Test Results:
- 41% of simulated users experience session-breaking events
- Recovery rate without persistence: 12%
- Data loss probability: 29%
Impact if Believed:
- Significant abandoned cart revenue loss
- User frustration and negative reviews
- Competitive disadvantage against persistent carts
Recommendation:
Implement cart persistence, resume functionality, email reminders
3. Assumption: "Fraud detection catches 99% of fraudulent transactions"
Status: ❌ BUSTED (Dangerously false)
Counterexamples Found:
- New fraud patterns not in training data (always emerging)
- Low-and-slow attacks evade threshold detection
- Synthetic identity fraud has no historical patterns
- Insider threats bypass external detection
- Collusion attacks distribute suspicious activity
Adversarial Testing Results:
- Simulated novel fraud: 67% detection rate (not 99%)
- Adaptive attackers: detection degrades over time
- False positive rate forces threshold lowering
- Detection latency allows transaction completion
Impact if Believed:
- Financial losses from undetected fraud
- Regulatory penalties for inadequate controls
- Reputation damage from fraud incidents
Recommendation:
Implement multi-layered fraud detection, continuous model updates
4. Assumption: "Database transactions always rollback on failure"
Status: ✅ WITHSTOOD TESTING (But edge cases found)
Stress Test Results:
- Normal failures: proper rollback (assumption holds)
- Edge Cases Discovered:
* Connection pool exhaustion during rollback
* Deadlock during distributed transaction cleanup
* Storage engine corruption preventing rollback
* Partial network failure leaving transactions dangling
Recommendation:
Implement transaction monitoring, orphan detection, manual cleanup procedures
Assumption Survival Rate:
- Completely Busted: 6 assumptions (43%)
- Partially Busted: 5 assumptions (36%)
- Withstood Testing: 3 assumptions (21%)
Critical Vulnerabilities Exposed:
1. Payment timeout handling (catastrophic failure possible)
2. Session persistence (significant revenue loss)
3. Fraud detection gaps (financial and regulatory risk)
4. Transaction cleanup (data consistency risk)
Busting Effectiveness Metrics:
- Novel failure modes discovered: 23
- Catastrophic scenarios identified: 7
- Previously unknown risks: 11
- Testing time vs value: Extremely high ROI
- Confidence adjustment: From 85% to 42% (more realistic)
Actionable Insights:
1. IMMEDIATE: Implement circuit breakers for payment gateway
2. HIGH PRIORITY: Add cart persistence and resume functionality
3. HIGH PRIORITY: Enhance fraud detection with behavioral analysis
4. MEDIUM PRIORITY: Add transaction monitoring and cleanup
5. MEDIUM PRIORITY: Create assumption registry with busting schedule
Next Busting Cycle Recommendations:
- Schedule: Monthly for critical assumptions
- Focus: New features and changed assumptions
- Method: Rotate between technical, business, process assumptions
- Participants: Include external perspectives for fresh eyes
Philosophical Notes:
- The assumptions that hurt most are those we don't know we're making
- A busted assumption is a gift - it reveals a hidden risk
- The goal isn't to prove assumptions wrong, but to find where they fail
- The most dangerous assumption is "our assumptions are mostly correct"
- Assumption busting creates antifragility - systems that improve when stressed
Notes
- Assumption busting is intentionally aggressive - it tries to break things
- Balance between thorough busting and practical constraints
- Document both busted assumptions and those that withstand testing
- Use busting findings to improve systems, not just criticize them
- The value is in discovering unknown unknowns
- Some assumptions should remain (but now you know their limits)
- Busting creates knowledge about system boundaries and failure modes
- Share busting results transparently to build organizational learning
- Regular assumption busting prevents accumulation of false beliefs
- The best busting often comes from outsiders with different perspectives
1---2name: assumption-buster3description: Aggressively challenge and attempt to disprove assumptions through counterexamples, edge cases, and adversarial thinking4license: MIT5compatibility: opencode6metadata:7 audience: developers, architects, security professionals8 category: critical-thinking9---1011# Assumption Buster1213Aggressively identify, challenge, and attempt to disprove assumptions through systematic counterexample generation, edge case exploration, and adversarial thinking to reveal hidden weaknesses and false beliefs.1415## When to use me1617Use this skill when:18- Critical decisions rely on untested assumptions19- Systems have high failure costs (safety, financial, reputation)20- You suspect team is suffering from confirmation bias21- Preparing for adversarial environments (security, competition, regulation)22- Testing resilience of core system beliefs23- Validating fundamental premises before major investments24- Challenging "industry best practices" that may not apply25- Stress-testing architectural decisions26- Preparing for audits, penetration tests, or regulatory reviews2728## What I do2930### 1. Assumption Aggression31- **Actively seek to disprove** rather than just test assumptions32- **Generate counterexamples** that break the assumption33- **Find edge cases** where assumption fails catastrophically34- **Identify contradiction patterns** in evidence35- **Pressure-test boundary conditions** until they break3637### 2. Disproof Methodology38- **Attempt falsification** using Popperian scientific method39- **Search for black swans** - rare but catastrophic counterexamples40- **Construct stress scenarios** that maximize assumption failure41- **Apply Murphy's Law** - "anything that can go wrong, will"42- **Explore combinatorial explosions** of failure modes4344### 3. Adversarial Testing45- **Think like an attacker** trying to break the system46- **Adopt competitor mindset** looking for weaknesses to exploit47- **Simulate hostile environments** (limited resources, malicious actors)48- **Test under extreme conditions** beyond design specifications49- **Provoke failure cascades** and ripple effects5051### 4. Cognitive Bias Countermeasures52- **Target confirmation bias** by seeking disconfirming evidence53- **Challenge availability heuristic** by looking for rare cases54- **Counter anchoring effect** by exploring extreme values55- **Overcome overconfidence** with rigorous stress testing56- **Break groupthink** by introducing dissenting perspectives5758## Assumption Busting Techniques5960### For Technical Assumptions:61- **Load to failure**: "What load breaks this assumption?"62- **Resource starvation**: "What happens with minimal resources?"63- **Dependency failure**: "What if every dependency fails simultaneously?"64- **Version hell**: "What if all versions are mismatched?"65- **Data corruption**: "What if data is intentionally malformed?"6667### For Business Assumptions:68- **Market reversal**: "What if customer preferences change overnight?"69- **Competitor innovation**: "What if a competitor solves this better/cheaper?"70- **Regulatory shock**: "What if regulations completely change?"71- **Economic collapse**: "What if funding disappears?"72- **Team dissolution**: "What if key people leave?"7374### For Process Assumptions:75- **Communication breakdown**: "What if all communication fails?"76- **Tool failure**: "What if primary tools become unavailable?"77- **Knowledge loss**: "What if institutional knowledge disappears?"78- **Timeline compression**: "What if deadlines move up 90%?"79- **Quality erosion**: "What if quality standards steadily decline?"8081## Examples8283```bash84# Aggressively test a technical assumption85npm run assumption-buster:disprove -- --assumption "database-always-available" --method "chaos-engineering"8687# Find counterexamples for a business assumption88npm run assumption-buster:counterexamples -- --assumption "users-prefer-mobile" --data "analytics-export.csv"8990# Stress-test architectural decisions91npm run assumption-buster:stress-test -- --architecture "event-driven" --scenario "complete-network-partition"9293# Generate failure scenarios for a process94npm run assumption-buster:failure-scenarios -- --process "ci-cd-pipeline" --intensity extreme9596# Comprehensive assumption busting97npm run assumption-buster:all -- --criticality high --thoroughness maximum98```99100## Output format101102```103Assumption Busting Report104──────────────────────────────105Target: Payment Processing System106Assumptions Targeted: 14107Busting Duration: 2 hours108Busting Intensity: Aggressive109110Assumption Busting Results:1111121. Assumption: "Payment gateway responses always within 2 seconds"113 Status: ❌ BUSTED (Catastrophically)114 115 Counterexamples Found:116 - Network partition causes indefinite hangs (no timeout)117 - Gateway DDoS attack results in 30+ second responses118 - SSL certificate expiration causes silent failures119 - DNS poisoning redirects to malicious endpoints120 - Gateway vendor bankruptcy (no responses at all)121 122 Stress Test Results:123 - Under simulated attack: 85% of requests exceed 2 seconds124 - Failure cascade: timeouts cause thread pool exhaustion125 - Worst-case latency: 47 seconds (complete system stall)126 127 Impact if Believed:128 - Payment system becomes unresponsive during attacks129 - Financial losses from failed transactions130 - Customer trust destroyed131 - Recovery requires complete system restart132 133 Recommendation:134 Implement circuit breakers, aggressive timeouts, fallback providers1351362. Assumption: "Users always complete checkout in single session"137 Status: ⚠️ PARTIALLY BUSTED (Significant weaknesses)138 139 Counterexamples Found:140 - Mobile network drops during payment (common)141 - Browser crashes after cart creation (frequent)142 - Users comparison shop across tabs (standard behavior)143 - Payment requires external verification (bank 2FA)144 - Users interrupted by real-world events (constant)145 146 Stress Test Results:147 - 41% of simulated users experience session-breaking events148 - Recovery rate without persistence: 12%149 - Data loss probability: 29%150 151 Impact if Believed:152 - Significant abandoned cart revenue loss153 - User frustration and negative reviews154 - Competitive disadvantage against persistent carts155 156 Recommendation:157 Implement cart persistence, resume functionality, email reminders1581593. Assumption: "Fraud detection catches 99% of fraudulent transactions"160 Status: ❌ BUSTED (Dangerously false)161 162 Counterexamples Found:163 - New fraud patterns not in training data (always emerging)164 - Low-and-slow attacks evade threshold detection165 - Synthetic identity fraud has no historical patterns166 - Insider threats bypass external detection167 - Collusion attacks distribute suspicious activity168 169 Adversarial Testing Results:170 - Simulated novel fraud: 67% detection rate (not 99%)171 - Adaptive attackers: detection degrades over time172 - False positive rate forces threshold lowering173 - Detection latency allows transaction completion174 175 Impact if Believed:176 - Financial losses from undetected fraud177 - Regulatory penalties for inadequate controls178 - Reputation damage from fraud incidents179 180 Recommendation:181 Implement multi-layered fraud detection, continuous model updates1821834. Assumption: "Database transactions always rollback on failure"184 Status: ✅ WITHSTOOD TESTING (But edge cases found)185 186 Stress Test Results:187 - Normal failures: proper rollback (assumption holds)188 - Edge Cases Discovered:189 * Connection pool exhaustion during rollback190 * Deadlock during distributed transaction cleanup191 * Storage engine corruption preventing rollback192 * Partial network failure leaving transactions dangling193 194 Recommendation:195 Implement transaction monitoring, orphan detection, manual cleanup procedures196197Assumption Survival Rate:198- Completely Busted: 6 assumptions (43%)199- Partially Busted: 5 assumptions (36%)200- Withstood Testing: 3 assumptions (21%)201202Critical Vulnerabilities Exposed:2031. Payment timeout handling (catastrophic failure possible)2042. Session persistence (significant revenue loss)2053. Fraud detection gaps (financial and regulatory risk)2064. Transaction cleanup (data consistency risk)207208Busting Effectiveness Metrics:209- Novel failure modes discovered: 23210- Catastrophic scenarios identified: 7211- Previously unknown risks: 11212- Testing time vs value: Extremely high ROI213- Confidence adjustment: From 85% to 42% (more realistic)214215Actionable Insights:2161. IMMEDIATE: Implement circuit breakers for payment gateway2172. HIGH PRIORITY: Add cart persistence and resume functionality2183. HIGH PRIORITY: Enhance fraud detection with behavioral analysis2194. MEDIUM PRIORITY: Add transaction monitoring and cleanup2205. MEDIUM PRIORITY: Create assumption registry with busting schedule221222Next Busting Cycle Recommendations:223- Schedule: Monthly for critical assumptions224- Focus: New features and changed assumptions225- Method: Rotate between technical, business, process assumptions226- Participants: Include external perspectives for fresh eyes227228Philosophical Notes:229- The assumptions that hurt most are those we don't know we're making230- A busted assumption is a gift - it reveals a hidden risk231- The goal isn't to prove assumptions wrong, but to find where they fail232- The most dangerous assumption is "our assumptions are mostly correct"233- Assumption busting creates antifragility - systems that improve when stressed234```235236## Notes237238- Assumption busting is intentionally aggressive - it tries to break things239- Balance between thorough busting and practical constraints240- Document both busted assumptions and those that withstand testing241- Use busting findings to improve systems, not just criticize them242- The value is in discovering unknown unknowns243- Some assumptions should remain (but now you know their limits)244- Busting creates knowledge about system boundaries and failure modes245- Share busting results transparently to build organizational learning246- Regular assumption busting prevents accumulation of false beliefs247- The best busting often comes from outsiders with different perspectives