Blast Radius Analysis
Analyze the impact of current code changes using the code knowledge graph.
Prerequisites
This skill requires the gauntlet plugin for graph data. Check if it's available:
GRAPH_QUERY=$(find ~/.claude/plugins -name "graph_query.py" -path "*/gauntlet/*" 2>/dev/null | head -1)If gauntlet is not installed (GRAPH_QUERY is empty): Fall back to a manual impact analysis using git diff and grep to trace imports and call sites. Skip graph steps and go directly to step 3 (manual mode).
If gauntlet is installed but no graph.db exists: Tell the user: "Run /gauntlet-graph build first."
Steps
- Show current changes: Run
git diff --statto
show the user what files changed.
- Run impact analysis (requires gauntlet):
``bash python3 "$GRAPH_QUERY" \ --action impact --base-ref HEAD --depth 2 ``
Fallback tier 1 (sem available, no gauntlet): Use sem for cross-file dependency tracing: ``bash if command -v sem &>/dev/null; then sem impact --json <changed-file> fi ``
This traces real function-level dependencies instead of filename matching. See leyline:sem-integration for detection patterns.
Fallback tier 2 (no sem, no gauntlet): Trace callers of changed functions with rg (or grep): ``bash # Prefer rg for speed; fall back to grep if command -v rg &>/dev/null; then git diff --name-only HEAD | while read f; do stem="${f%.}"; stem="${stem##/}" [ -z "$stem" ] && continue # skip dotfiles (.gitignore etc.) rg -l "$stem" . 2>/dev/null done | sort -u else git diff --name-only HEAD | while read f; do stem="${f%.}"; stem="${stem##/}" [ -z "$stem" ] && continue # skip dotfiles (.gitignore etc.) grep -rl "$stem" . 2>/dev/null done | sort -u fi ``
Note: this searches all file types. For Python-only projects, add --type py to rg or --include="*.py" to grep to reduce false positives.
- Display results in priority order:
Format the output as a table: `` Risk | Node | File | Reason 0.85 | auth.py::verify_token | auth.py:45 | untested, security 0.62 | db.py::execute_query | db.py:112 | high fan-in 0.41 | api.py::handle_request | api.py:78 | flow participant ``
- Highlight untested functions: List any affected
functions that lack test coverage (no TESTED_BY edge).
- Show overall risk: Display the overall risk level
(low/medium/high) based on the maximum risk score.
- Suggest actions:
- For high-risk nodes: "Consider adding tests before
merging"
- For security-sensitive nodes: "Review authentication
and authorization logic carefully"
- For high-fan-in nodes: "Changes here affect many
callers; verify backward compatibility"
Risk Scoring Model
Five weighted factors (sum capped at 1.0):
| Factor | Weight | Meaning | |--------|--------|---------| | Test gap | 0.30 | No test coverage | | Security | 0.20 | Auth/crypto/SQL keywords | | Flow participation | 0.25 | Part of execution flows | | Cross-community | 0.15 | Called from other modules | | Caller count | 0.10 | High fan-in function |