How to Answer the 9 Questions
Don't guess. Inspect your system. Answer based on evidence.
How to Answer:
YES → You can verify this with logs / system behavior
PARTIAL → Exists but incomplete or inconsistent
NO → No evidence or not enforced
1. Replayability
Where to check:
Decision logs, input/output snapshots, stored metadata
Test:
Take one past decision → try to reproduce it exactly
YES → Same input produces same decision exactly
NO → You cannot fully reconstruct the decision
2. Determinism
Where to check:
Model behavior, randomness, time-based inputs
Test:
Run same input multiple times
YES → Output is identical every time
NO → Output changes across runs
3. Ownership
Where to check:
System design, service responsibility, team ownership
Test:
Ask: Who is accountable for this decision?
YES → Clear owner exists
NO → Responsibility unclear
4. Authority Boundaries
Where to check:
Permission checks, role validation
Test:
Can system act without explicit permission?
YES → Action blocked without permission
NO → System assumes authority
5. Failure Safety
Where to check:
Error handling, rollback logic
Test:
Force a failure mid-process
YES → System returns to safe state
NO → Partial or corrupted state remains
6. Idempotency
Where to check:
API design, request handling
Test:
Send same request multiple times
YES → Only one execution happens
NO → Duplicate actions occur
7. State Validity
Where to check:
Input validation, timestamps, completeness checks
Test:
Remove or delay key input data
YES → System blocks decision
NO → System still proceeds
8. Authority Validity
Where to check:
Access control at execution time
Test:
Try executing with expired/invalid permission
YES → System blocks action
NO → System allows action
9. State Continuity
Where to check:
Data lineage, audit trails
Test:
Trace decision back to original source
YES → Full trace exists
NO → Missing or broken lineage
If you cannot verify it → it is NOT a YES.