failure-propagation-analyzer

name	failure-propagation-analyzer
description	Analyze likely cascade paths and propagation semantics in DSDS architectures. Use when estimating blast radius, diagnosing multi-hop degradation, validating containment strategies, or explaining how a localized failure can become systemic.

Failure Propagation Analyzer

Overview

Model how failures spread through dependencies and identify where containment should happen. Produce an explicit trigger-to-impact chain with mitigation points.

Workflow

1. Build dependency view

• Identify upstream/downstream relationships and critical dependencies.
• Mark optional fallbacks and graceful degradation paths.

2. Define trigger failure

• Choose initiating failure type and target component.
• Record timing and intensity assumptions.

3. Apply propagation semantics

• Evaluate timeouts, retries, queue growth, resource exhaustion, and split-brain risks.
• Track each hop with expected delay and effect.

4. Estimate blast radius

• Identify directly affected components, second-order impacts, and user-facing outcomes.
• Distinguish local degradation from system-wide risk.

5. Propose containment

• Recommend controls: bulkheads, breakers, timeouts, backpressure, and load shedding.
• Prioritize controls by impact reduction and implementation effort.

Output format

1. Trigger definition
2. Propagation chain
3. Blast radius summary
4. Containment recommendations
5. Confidence and assumptions

References

• Read references/propagation-modeling-checklist.md for analysis checklist.
• Use these repo sources:
• canonical-catalogue/DSDS Canonical Catalogue - Failure modes & propagation semantics.csv
• docs/04-distributed-systems-and-failures.md (Chapters 22-24)
• planning/IMPLEMENTATION_PLAN.md (Phase 4)