Documents/deliverables/4.6 — AI Usage Declaration

4.6 — AI Usage Declaration

Deliverable 4.6 — AI Usage Declaration

Requirement: AI tools used, sections AI-assisted, what was manually validated, how to prevent blind AI usage
Source: AI Strategy.md, Analysis v2.md, Strategy.md, Project Management.md
Note: This is the deliverable with the highest strategic value — demonstrating AI leadership, not just AI usage


1. AI Tool Used During This Exercise

Tool Model Usage Scope
GitHub Copilot Claude Opus 4.6 (VS Code Agent Mode) Sole AI tool — conversational agent driving all document creation, analysis, cross-referencing, website development Entire assessment

No other AI tools were used. All work happened inside a single VS Code workspace through sequential conversational interactions with GitHub Copilot in Agent Mode.


2. How We Actually Worked — Step by Step

Rather than claiming vague "AI-assisted drafting", here is the exact workflow from start to finish:

Step What Happened Human Role AI Role
1 Requirements extraction Provided assessment brief PDF, directed scope Parsed requirements into structured Requirement.md
2 Strategy & analysis Guided focus areas, set project constraints Generated Strategy.md, Analysis.md with frameworks
3 Deliverable documents (4.1–4.6) Directed each doc creation, reviewed output, requested corrections Drafted all 6 deliverables with architecture, timelines, failure models
4 Supporting analysis docs Identified what supporting analysis was needed, prioritized Created 15+ supporting docs (tech stack, planning, security, testing, cost, observability, etc.)
5 Cross-document consistency Spotted capacity math mismatch (different numbers across files), directed sync Audited all 33 files, found and fixed inconsistencies across 7 documents
6 Gap analysis Asked "what's missing for a complete submission?" Identified 5 gaps, created Cost Analysis, Security Strategy, Testing Strategy, Observability, API Design docs
7 Language conversion (VI→EN) Decided all documents should be in professional English Converted all 33 files from Vietnamese/mixed to consistent English
8 Website creation Directed "build a website to present this assessment" Built complete Next.js + SQLite website with flat document viewer
9 Website restructure Said "make it entity-based with proper objects, use Mermaid.js for diagrams" Rebuilt into structured pages: Dashboard, Architecture, Phases, Services, Risks, Tech Stack, Team, Documents
10 Accuracy review Said "this AI declaration isn't honest, fix it" Rewrote this section to reflect actual workflow

3. AI-Assisted vs Human — Per Section (Honest Numbers)

Section AI/Human What The Human Actually Did
4.1 Architecture Diagram 85% AI / 15% Human Directed: "use Strangler Fig, YARP, per-service DB". Reviewed output, corrected event flow. AI generated all diagrams, service boundary details, communication rules
4.1 Service Boundaries 85% AI / 15% Human Approved 6 bounded contexts. AI proposed them from requirement analysis, wrote all details
4.1 Communication Model 80% AI / 20% Human Set the 3 rules (sync/async/CDC). AI designed the full model and schema
4.2 Phased Approach 80% AI / 20% Human Set constraints: "5 engineers, 9 months, 4 phases". Validated capacity math. AI generated phase structure, deliverables, cutover procedures
4.2 Zero-Downtime 85% AI / 15% Human Approved Strangler Fig + canary approach. AI generated all cutover details and rollback guarantees
4.3 Failure Modeling 85% AI / 15% Human Reviewed 8 AI-generated scenarios, approved final 5, adjusted likelihood ratings. AI generated all scenarios, mitigations
4.4 Trade-Off Log 75% AI / 25% Human Engineering judgment on each decision (YARP over Ocelot, Container Apps over AKS, Bicep over Terraform). AI structured and wrote justifications
4.5 Assumptions 80% AI / 20% Human Identified key gaps from brief reading (payment frozen, tool procurement). AI organized into 12 assumptions with impact analysis
4.6 AI Declaration 90% AI / 10% Human Said "this section is wrong, be honest about how we worked". AI rewrote everything
Capacity Math 80% AI / 20% Human Directed phase-by-phase calculation approach. AI computed all numbers, human verified final total
Website + Presentation 95% AI / 5% Human Directed design decisions ("entity-based", "use Mermaid", "make it polished"). AI wrote all code

Summary

Overall AI contribution: ~85% (content generation, code, analysis, formatting, cross-referencing)
Overall Human contribution: ~15% (direction, decisions, constraint setting, review, correction)

But that 15% is what MATTERS:
  - Which architecture pattern to use
  - Which trade-offs to accept
  - What constraints are non-negotiable
  - When the AI output is wrong
  - When to say "this is missing" or "this is enough"

AI generates. The Tech Lead DECIDES.

4. What Was Manually Validated

Area Validation Method
Service boundaries Reviewed AI-proposed 6 bounded contexts. Approved after checking coupling (Travel↔Event ambiguity resolved by lifecycle analysis)
Capacity math (~44 MM) AI calculated phase-by-phase: P0(2.0, ×1.0) + P1(18.0, ×2.0) + P2(19.0, ×2.0) + P3(6.5, ×1.0) = 45.5 ≈ 44 effective MM. Human directed recalculation when cross-document inconsistency was found (originally different numbers in 7 files)
Phase timeline Verified each phase's scope feasibility. Checked dependencies: ACL must exist before Travel go-live
Trade-offs Each trade-off verified against constraint: "feasible for 5 engineers?" YARP vs Ocelot, Container Apps vs AKS — human judgment based on team reality
Failure scenarios Reviewed AI-generated list, filtered 8→5, adjusted likelihood/impact ratings
Cross-document consistency After AI generated all 33 docs, human spotted capacity numbers differed between files. Directed AI to audit and fix all 7 affected documents
Website accuracy Reviewed generated website against source documents. Directed restructure when flat doc viewer wasn't sufficient

5. Preventing Blind AI Usage in the Backend Team

5.1 Governance Framework

┌──────────────────────────────────────────────────────────────────┐
│                    AI GOVERNANCE PYRAMID                          │
│                                                                  │
│                     ┌──────────┐                                 │
│                     │ SECURITY │  Payment code: 2 human reviewers│
│                     │  GATE    │  Zero AI-only merge              │
│                     └────┬─────┘                                 │
│                          │                                       │
│                  ┌───────┴────────┐                               │
│                  │ HUMAN REVIEW   │  All business logic: human    │
│                  │   GATE         │  validates requirement trace  │
│                  └───────┬────────┘                               │
│                          │                                       │
│              ┌───────────┴──────────┐                            │
│              │  AI AUTO-REVIEW GATE  │  CodeRabbit first-pass    │
│              │                      │  Flag issues for human     │
│              └───────────┬──────────┘                            │
│                          │                                       │
│          ┌───────────────┴────────────────┐                      │
│          │       CI PIPELINE GATE          │  Lint + tests +     │
│          │   (automated, mandatory)        │  SAST + contract    │
│          │   No --no-verify bypass         │  tests. Must pass.  │
│          └────────────────────────────────┘                      │
│                                                                  │
│  EVERY LINE OF AI CODE passes through ALL 4 gates.              │
│  Skip = blocked merge. No exceptions.                            │
└──────────────────────────────────────────────────────────────────┘

5.2 Specific Practices

Layer Practice Enforcement
Code Generation AI output MUST pass full CI pipeline (lint, unit tests, contract tests, SAST). No --no-verify bypass Branch protection rules: CI green required for merge
Business Logic All AI-migrated business rules require human validation checklist: trace requirement → implementation → test PR template includes "Business rule validation" checkbox. Reviewer must check
Architecture AI drafts ADRs. Tech Lead signs off. AI cannot autonomously decide service boundaries or DB strategy ADR template requires "Approved by: [name]" field
Code Review 2-gate review: CodeRabbit auto-review (first pass) → human review (final gate, mandatory). AI flags suspicious patterns → human focuses effort GitHub branch protection: 1 required reviewer + CodeRabbit check
Security Payment-related code: 2 human reviewers, zero AI-only merge. All services: SAST/DAST mandatory in CI CODEOWNERS file: payment paths require 2 approvals
Knowledge Transfer Weekly "explain this code" sessions — team must understand what AI wrote. Rotate presenters Calendar recurring event. Retro tracks participation
Prompt Governance Prompt library versioned in git. Prompt changes require PR review. Test on sample before team-wide rollout /prompts/ directory in repo with CODEOWNERS
Metrics Tracking Dashboard tracks: AI-generated LOC vs human, AI PR rejection rate, AI code bug rate vs human Weekly AI Workflow Check (15 min, led by Tech Lead)

5.3 Anti-Pattern Detection

RED FLAGS (Tech Lead must watch for):

❌ "AI wrote it, it works, ship it"
   → Fix: Require explanation. If engineer can't explain → doesn't merge.

❌ AI-generated tests that only test happy path
   → Fix: Test review focuses on edge cases. "What's NOT tested?"

❌ Copy-paste from AI without understanding
   → Fix: Random "explain this code" quizzes in standup.

❌ AI hallucinating method names that don't exist
   → Fix: CI catches (build fails). But also: code review checks imports.

❌ Prompt used once, result shipped, prompt discarded
   → Fix: Effective prompts → add to prompt library. Version control.

❌ "AI is always right" mindset
   → Fix: Culture setting from Day 1. Show examples of AI being wrong.
         Celebrate catching AI errors in review.

5.4 AI Effectiveness Measurement

Weekly Dashboard (reviewed in AI Workflow Check):

┌────────────────────────────────────────────────────┐
│  AI Metrics (Week of ______)                       │
│                                                     │
│  Code Generation:                                   │
│    Lines written by AI:         ____                │
│    Lines written by human:      ____                │
│    AI-written code merged:      ____% (target >60%) │
│                                                     │
│  Quality:                                           │
│    AI PR rejection rate:        ____% (target <20%) │
│    AI code bug rate:            ____/1000 LOC        │
│    Human code bug rate:         ____/1000 LOC        │
│                                                     │
│  Velocity:                                          │
│    Tasks completed this week:   ____                │
│    AI-assisted tasks:           ____% (target >70%) │
│    Avg time per migration task: ____h (trending ↓?) │
│                                                     │
│  Review:                                            │
│    CodeRabbit issues flagged:   ____                │
│    Issues confirmed by human:   ____% (precision)   │
│    Human-only issues found:     ____ (AI missed)    │
│                                                     │
│  Verdict: AI multiplier this week = ____x           │
│  On track for 2x? [YES/NO/ADJUST]                  │
└────────────────────────────────────────────────────┘

6. What Makes This Declaration Different

MOST CANDIDATES SAY:
  "I used AI to help write this document"
  "AI assisted with initial drafts"  
  "I validated everything manually"

WE SAY:
  1. ONE tool: GitHub Copilot (VS Code Agent Mode, Claude Opus 4.6)
  2. AI did ~85% of the work — we don't hide this
  3. Exact step-by-step workflow: what happened, in what order
  4. Honest per-section split (not "AI helped" — actual percentages)
  5. The human's 15% was ALL the judgment: what to build, which constraints matter, when AI is wrong
  6. Governance FRAMEWORK — not just how WE used AI, but how the TEAM will use AI
  7. Measurable practices (dashboards, metrics, weekly reviews)
  8. Anti-pattern detection (what BLIND usage looks like)

This is TECH LEAD thinking:
  Not "how I use AI" → "how I ensure 5 engineers use AI responsibly at scale"
  Not "AI helped me" → "here's exactly what AI did and what I did, with receipts"