An application-level failure arises from application semantics or business rules rather than the underlying platform. An InsufficientFunds response is meaningful to the application but not to lower platform layers. section 3.3.3
Classify a failure by asking which lowest layer can detect and mitigate it correctly and completely. That layer owns the response. section 3.3.3
Application-level failures shape both detection and recovery:
- Detect them from application outcomes such as a step’s return code or an InsufficientFunds response. section 3.3.4
- Mitigate them in the application layer; backward recovery can compensate for steps that already occurred. section 3.3.6
- Escalate failures that remain unresolved during recovery to the human layer for operational intervention. section 3.3.6
Insufficient funds versus connectivity
A credit-card charge returning InsufficientFunds requires application-level handling because the business meaning belongs to the application. A CouldNotConnect response is platform-level because the platform can retry the connection. section 3.3.3 section 3.3.4
Figure 3.10 Application-level vs. platform-level failure
Use the layer comparison to locate application-level failure beside platform-level failure and identify the responsible mitigation layer. section 3.3.3
