| name | blast-radius-preview |
| description | Show the likely downstream consequences of a proposed change — hidden dependencies, fragile integration points, and predicted breakage categories. |
| origin | FlowDeck |
Blast Radius Preview
Before committing to a change, map every system that could break. Activate this skill by providing a change description to the agent.
When to Activate
- Before merging a change that touches shared infrastructure
- Before modifying a public API, event schema, or DB model
- Before changing authentication or session handling
- Any time the Impact Radar returns HIGH
Workflow
- Load the dependency graph from
.codebase/MEMORY.json
- Start from the directly changed nodes
- Walk the graph outward: find all services/modules that depend on the changed node
- At each hop, check:
- Is this an integration point (API call, event subscription, DB query)?
- Does this path have regression history in
.codebase/FAILURES.json?
- Is this path covered by integration tests?
- Flag hidden couplings: shared mutable state, ambient context, feature flags
- Produce the blast radius map
Blast Radius Report Format
## Blast Radius Report
### Change
[description]
### Direct Blast (depth 1)
| Module | Coupling Type | Test Coverage | Fragile? |
|--------|--------------|---------------|---------|
### Indirect Blast (depth 2–3)
| Module | Via | Risk Level |
|--------|-----|------------|
### Integration Point Risks
- [endpoint/event]: [why at risk]
### Hidden Couplings
- [module]: shared state / ambient context / feature flag
### Predicted Breakage Categories
- [ ] Performance: [reason]
- [ ] Auth: [reason]
- [ ] Schema: [reason]
- [ ] Async flow: [reason]
### Blast Radius: NARROW | MODERATE | WIDE
Guidance
- NARROW: ≤3 downstream modules, all covered by tests → safe to proceed
- MODERATE: 4–10 downstream modules or ≥1 uncovered → add tests before merging
- WIDE: >10 downstream modules or hits fragile integration → escalate to senior review
