Analyse the blast radius of a change to a requirement, decision, or design document
You are helping an enterprise architect understand the blast radius of a change to an existing requirement, decision, or design document. This is reverse dependency tracing — the complement of forward traceability.
$ARGUMENTS
Note: The ArcKit Impact hook has already built a dependency graph from all project artifacts and provided it as structured JSON in the context. Use that data — do NOT scan directories manually.
Parse the query to identify the change source:
ARC-001-REQ, ARC-001-ADR-003) → find all documents that reference itBR-003, NFR-SEC-001) → find all documents containing that requirement IDADR --project=001) → show all dependencies of ADRs in that projectPerform reverse traversal using the dependency graph:
Classify impact severity using the severity field from the graph nodes:
Output format (console only — do NOT create a file):
## Impact Analysis: BR-003 (Data Residency Requirement)
### Change Source
- **Requirement:** BR-003 — "All customer data must reside within UK data centres"
- **Defined in:** ARC-001-REQ-v2.0 (projects/001-payments/)
### Impact Chain
| Level | Document | Type | Impact | Action Needed |
|-------|----------|------|--------|---------------|
| 1 | ARC-001-ADR-002-v1.0 | ADR | MEDIUM | Review cloud provider decision |
| 1 | ARC-001-HLDR-v1.0 | HLDR | MEDIUM | Update deployment architecture |
| 2 | ARC-001-SECD-v1.0 | SECD | HIGH | Re-assess data protection controls |
| 2 | ARC-001-DPIA-v1.0 | DPIA | HIGH | Re-run DPIA assessment |
| 3 | ARC-001-OPS-v1.0 | OPS | LOW | Check operational procedures |
### Summary
- **Total impacted:** 5 documents
- **HIGH severity:** 2 (compliance re-assessment needed)
- **MEDIUM severity:** 2 (design updates needed)
- **LOW severity:** 1 (review recommended)
### Recommended Actions
1. Re-run `$arckit-secure` to update Secure by Design assessment
2. Re-run `$arckit-dpia` to update Data Protection Impact Assessment
3. Review ADR-002 decision rationale against updated requirement
Recommend specific /arckit: commands for HIGH severity impacts:
$arckit-secure$arckit-dpia$arckit-tcop$arckit-hld-review$arckit-risk$arckit-traceabilityIf no impacts found, report that the document has no downstream dependencies. Note this may indicate a traceability gap — suggest running $arckit-traceability to check coverage.
If the query matches multiple documents, list them and ask the user to specify which one to analyse.
After completing this command, consider running:
$arckit-traceability -- Update traceability matrix after impact assessment (when Impact analysis revealed traceability gaps)$arckit-health -- Check health of impacted artifacts (when Impacted documents may be stale)$arckit-conformance -- Re-assess conformance after changes (when Impact includes architecture design documents)