| name | gitnexus-impact |
| description | Blast radius analysis — what breaks if you change a symbol. Triggers: "impact analysis" | "what breaks if" | "blast radius" | "gitnexus impact" | "is it safe to change" | "dependencies of". |
GitNexus Impact
Blast radius analysis: find what breaks if you change a symbol. Essential before refactoring.
Entry
/gitnexus-impact validateUser
/gitnexus-impact AuthService --direction downstream
/gitnexus-impact processOrder --depth 2
¬symbol → ask user provide a symbol name.
Step 0 — Pre-flight
gitnexus status
¬indexed → ask user run /gitnexus-analyze first.
Step 1 — Run Impact Analysis
gitnexus impact "$SYMBOL" $FLAGS
| Flag | Effect |
|---|
--direction upstream | Who depends on this (default) |
--direction downstream | What this depends on |
--depth N | Max relationship depth (default: 3) |
--include-tests | Include test files |
--repo <name> | Target specific repo |
Step 2 — Parse JSON Output
{
"target": "validateUser",
"direction": "upstream",
"callers": [
{
"name": "loginHandler",
"file": "src/auth/login.ts",
"line": 42,
"depth": 1,
"confidence": 1.0
}
],
"risk_level": "HIGH",
"affected_processes": ["LoginFlow", "TokenRefresh"],
"summary": {
"d1_count": 2,
"d2_count": 5,
"d3_count": 12
}
}
Step 3 — Present Results
Target: validateUser
Direction: upstream (what depends on this)
Risk Level: HIGH
Depth 1 — WILL BREAK (direct callers):
| Symbol | File | Line |
|---|
| loginHandler | src/auth/login.ts | 42 |
| apiMiddleware | src/api/middleware.ts | 15 |
Depth 2 — LIKELY AFFECTED:
| Symbol | File |
|---|
| authRouter | src/routes/auth.ts |
| sessionManager | src/auth/session.ts |
Depth 3 — MAY NEED TESTING:
12 transitive dependencies...
Affected Processes: LoginFlow, TokenRefresh
Step 4 — Risk Assessment
| Affected | Risk |
|---|
| <5 symbols, few processes | LOW |
| 5-15 symbols, 2-5 processes | MEDIUM |
| >15 symbols or many processes | HIGH |
| Critical path (auth, payments) | CRITICAL |
HIGH or CRITICAL risk → warn user before proceeding with edits.
Step 5 — Recommendation
- LOW: Safe to edit, verify tests pass
- MEDIUM: Review d=1 items, update them, run integration tests
- HIGH: Draft plan, update all d=1 callers, full test suite
- CRITICAL: Flag to user — may need broader coordination
$ARGUMENTS
