API DESIGN REVIEW SCORECARD FOR V2 LAUNCH:

CONSISTENCY AUDIT
   Naming conventions:
   ✓ Nouns for resources: GET /v2/accounts, POST /v2/invoices
   ✓ Verbs as subresources: POST /v2/accounts/123/invite
   ✓ Snake_case for fields: created_at, account_id, not createdAt
   
   Response format:
   ✓ Success: { status: 'success', data: {...} }
   ✓ Error: { status: 'error', code: 'VALIDATION_FAILED', message: '...' }
   ✓ All endpoints return consistent wrapper (no inconsistent raw arrays)

BREAKING CHANGES DETECTED
   1. BLOCKER: GET /v1/reports → removed, no deprecation period
      → Add v1 endpoint with 301 redirect to v2
   2. WARNING: POST /v2/accounts now requires 'billing_email' (was optional)
      → Add default behavior or deprecation warning header
   3. MINOR: Response field 'user_count' renamed to 'active_users'
      → Include both fields in transition period

DESIGN SMELLS FOUND
   • Endpoint GET /v2/accounts/search missing pagination (could return 100K+ results)
     → Add limit/offset parameters
   • PATCH /v2/invoices accepts full invoice object, but only updates 3 fields
     → Clarify docs which fields are patchable

DESIGN SCORECARD
   Endpoint consistency: 9/10 (naming and structure clear)
   Documentation completeness: 7/10 (missing error code glossary)
   Versioning strategy: 8/10 (no sunset date for v1)
   Security: 8/10 (missing rate-limit headers in response)
   
   RECOMMENDATION: Ship v2 after fixing breaking-change warnings