Analyze-Impact 150 Protocol
Core Principle: Understand the ripple effects. See how changes in one part affect the whole system.
What This Skill Does
When you invoke this skill, you're mapping:
- •Core — What exactly is being changed
- •Impact — What will be affected by the change
- •Dependencies — What the core depends on and what depends on it
- •Boundaries — Where the effects stop
The Impact Model
[UPSTREAM]
What the core depends on
↓
[CORE] ←── What we're changing
↓
[DOWNSTREAM]
What depends on the core
↓
[BOUNDARIES]
Where effects fade out
The 150% Impact Rule
- •100% Core: Complete understanding of what's being changed
- •50% Enhancement: Clear view of dependencies and downstream effects
When to Use This Skill
Universal trigger: Anytime you need to understand impact and dependencies.
Specific triggers:
- •Before making changes to code/systems
- •When debugging to understand cause chains
- •Planning features that touch multiple parts
- •Refactoring decisions
- •Risk assessment
- •Understanding legacy systems
- •When you hear "why did changing X break Y?"
Key insight: Impact mapping prevents surprises. Changes don't happen in isolation.
The Impact Layers
| Layer | Description | Coverage |
|---|---|---|
| Core | What's directly changing | 100% — must fully understand |
| Immediate | Direct dependencies and users | 50% — must assess |
| Extended | Secondary effects | 25% — should consider |
| System | Full ecosystem | 10% — be aware |
Execution Protocol
Step 1: DEFINE CORE
Clearly identify what's changing:
- •What exactly is being modified?
- •What files/components/systems?
- •What's the nature of the change?
Step 2: MAP UPSTREAM
Identify dependencies (what the core needs):
- •What does this component use?
- •What must exist for this to work?
- •What configurations/data/services?
Step 3: MAP DOWNSTREAM
Identify dependents (what uses the core):
- •Who/what uses this component?
- •What breaks if this changes?
- •What needs to be updated?
Step 4: TRACE RIPPLES
Follow the effects outward:
- •What do the downstreams depend on?
- •Where do effects stop?
- •What's the blast radius?
Step 5: MARK BOUNDARIES
Define where impact ends:
- •What's definitely NOT affected?
- •Where can we safely stop analyzing?
- •What's the "fence" around the change?
Impact Mapping Questions
About the Core:
- •"What exactly is changing?"
- •"What's the nature of the change?"
- •"Is it additive, modifying, or removing?"
About Upstream (Dependencies):
- •"What does this use/import/call?"
- •"What must exist for this to work?"
- •"What configs/data does it need?"
About Downstream (Dependents):
- •"What uses/imports/calls this?"
- •"What would break if this changes?"
- •"Who relies on this behavior?"
About Boundaries:
- •"Where do the ripples stop?"
- •"What's definitely unaffected?"
- •"What's the maximum blast radius?"
Output Format
When using Impact-Map 150:
🗺️ **Impact-Map 150 Complete** **Core Change:** [What exactly is being changed] **Upstream Dependencies:** - [What this needs to work] - [Required services/data/configs] **Downstream Impact:** - 🔴 Critical: [What definitely breaks] - 🟡 Affected: [What needs checking] - 🟢 Monitor: [What might be touched] **Boundaries:** - Impact stops at: [clear boundary] - Definitely safe: [unaffected areas] **Blast Radius:** [Small/Medium/Large/System-wide] **Risks Identified:** - [What could go wrong] Ready to proceed with awareness.
Visual Impact Map
Example: Changing User Authentication
[Config Files] [Environment Vars]
↓ ↓
┌─────────────────────────────┐
│ 🎯 CORE: Auth Module │
└─────────────────────────────┘
↓ ↓ ↓
[Login API] [Session Mgmt] [Token Gen]
↓ ↓ ↓
┌──────────────────────────────────┐
│ 🔴 CRITICAL: All Authenticated │
│ Endpoints, User Sessions │
└──────────────────────────────────┘
↓ ↓
┌──────────────────────────────────┐
│ 🟡 AFFECTED: Mobile App, Web App │
│ Admin Panel, API Clients │
└──────────────────────────────────┘
↓
┌──────────────────────────────────┐
│ 🟢 BOUNDARY: Analytics, Logging │
│ (may need token format update)│
└──────────────────────────────────┘
Operational Rules
- •CORE FIRST: Always clearly define what's changing before mapping impact
- •TRACE BOTH WAYS: Map upstream (dependencies) AND downstream (dependents)
- •MARK BOUNDARIES: Know where the impact stops
- •ESTIMATE BLAST RADIUS: Understand the scale of potential effects
- •DOCUMENT SURPRISES: Note unexpected connections discovered
- •VALIDATE WITH CODE: Don't guess — check actual imports/usage
Examples
❌ Without Impact Mapping
Task: "Update the date format in utils.js" Action: Changed format from 'MM/DD/YYYY' to 'YYYY-MM-DD' Result: 47 pages broke, 3 API integrations failed, customer reports corrupted Why: Didn't map what used that utility
✅ With Impact-Map 150
Task: "Update the date format in utils.js" 🗺️ Impact-Map 150: Core: formatDate() in utils.js Upstream Dependencies: - moment.js library - locale config Downstream Impact: - 🔴 Critical: Invoice generation (uses formatDate) - 🔴 Critical: API responses (15 endpoints) - 🟡 Affected: All UI date displays (23 components) - 🟢 Monitor: Log timestamps Boundaries: - Database stores as ISO, unaffected - External APIs have their own formatting Blast Radius: Large — touches most of UI Action: Create formatDateNew(), migrate gradually, deprecate old
Failure Modes & Recovery
| Failure | Detection | Recovery |
|---|---|---|
| Missed dependency | Something breaks unexpectedly | Expand upstream mapping |
| Missed dependent | Users complain after change | Trace all usages with grep/IDE |
| Underestimated blast | "Small change" causes chaos | Re-map with wider scope |
| Unclear boundaries | Don't know what's safe | Explicitly mark boundaries |
Relationship to Other Skills
| Skill | Focus |
|---|---|
| goal-clarity-150 | WHAT we want to achieve |
| deep-think-150 | HOW to think about it |
| impact-map-150 | WHAT it affects |
| max-quality-150 | HOW to do it well |
Workflow:
goal-clarity-150 → impact-map-150 → deep-think-150 → max-quality-150
↓ ↓ ↓ ↓
Understand Map what's Think Execute
the goal affected through well
Session Log Entry (MANDATORY)
After completing this skill, write to .sessions/SESSION_[date]-[name].md:
### [date - HH"MM] Analyze-Impact 150 Complete **Core Change:** <what is changing> **Blast Radius:** <Small/Medium/Large> **Key Dependencies:** <critical up/downstream> **Risks:** <identified risks>
Remember: Every change has ripple effects. The question isn't "will something else be affected?" but "what will be affected and how much?" Impact mapping turns surprises into planned awareness.