AG08 is an architectural vulnerability — not a bug in any individual agent. Each agent can work correctly while the system still lacks the isolation mechanisms that prevent failure propagation.

Silent failures are the hardest to defend against. A structurally valid output with wrong content passes every format check and enters the pipeline undetected — only content validation or semantic sanity checks catch it.

Circuit breakers are the most broadly applicable control. They appear as a primary mitigation for 4 of 6 failure patterns — they are the architectural pressure relief valve that every multi-agent pipeline needs.

Fixed-interval retry without jitter reliably extends outages. The thundering herd pattern means that simultaneous retries from multiple agents repeatedly overwhelm recovering dependencies — exponential backoff with jitter is non-negotiable.

The blast radius of a cascading failure grows linearly with time-to-detection. Rate limiting and human confirmation gates for bulk terminal actions are not overhead — they limit how much irreversible harm accumulates before detection.

Monitoring must be independent of what it monitors. A monitoring agent that shares its LLM API provider with the pipeline it watches will be unavailable during exactly the outage it's supposed to detect.