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+---
+title: "Monitoring & Costs — Navigation Structure"
+version: 3.8.6
+lastUpdated: 2026-05-28
+---
+
+# Monitoring & Costs — Navigation Structure
+
+> Implemented in Group B (plan 16). See `src/shared/constants/sidebarVisibility.ts`.
+
+---
+
+## High-Level Navigation
+
+The dashboard sidebar (after Group B) has these top-level sections in order:
+
+```
+Home
+Providers
+Combos
+API Keys
+Settings
+Analytics
+Costs          ← NEW (Group B, plan 16)
+Monitoring     ← REORGANIZED (Group B, plan 16)
+...
+```
+
+---
+
+## Costs section (new, level 1)
+
+Path prefix: `/dashboard/costs/`
+
+| Item | URL | Description |
+|------|-----|-------------|
+| Overview | `/dashboard/costs` | Aggregated cost dashboard (moved from Analytics) |
+| Pricing | `/dashboard/costs/pricing` | Per-model pricing table |
+| Budget | `/dashboard/costs/budget` | Budget thresholds + alerts |
+| Quota Sharing | `/dashboard/costs/quota-share` | Quota Share pools + usage |
+| Plan Config | `/dashboard/costs/quota-share/plans` | Per-provider plan overrides |
+
+**Rationale**: Pricing, Budget, and Quota Sharing were previously under
+`Monitoring > Costs Parameters`. Moving them to a dedicated top-level section
+makes them discoverable without navigating through observability tooling.
+
+---
+
+## Monitoring section (reorganized)
+
+The Monitoring section now has **Activity at the top** followed by **3 subgroups**:
+
+```
+Monitoring
+├── Activity             ← Timeline feed (top-level item)
+├── Logs group
+│   ├── Logs (all)
+│   ├── Proxy Logs
+│   └── Console Logs
+├── Audit group
+│   ├── Audit Log
+│   ├── MCP Audit
+│   └── A2A Audit
+└── System group
+    ├── Health
+    └── Runtime
+```
+
+### What changed from the old structure
+
+| Before | After |
+|--------|-------|
+| Activity = tab inside Logs that rendered the Audit Log | Activity = dedicated feed (`/dashboard/activity`) |
+| Costs Parameters group in Monitoring | Moved to Costs section |
+| Flat list: Logs, Activity (logs), Audit, Health, Runtime, Pricing, Budget, Quota | Structured 3-group + dedicated Costs section |
+
+---
+
+## Activity vs Audit Log
+
+These two are now distinct:
+
+| Dimension | Activity (`/dashboard/activity`) | Audit Log (`/dashboard/audit`) |
+|-----------|----------------------------------|-------------------------------|
+| **Purpose** | User-facing event feed ("what happened recently") | Compliance / security log |
+| **Data source** | `GET /api/compliance/audit-log?level=high` | `GET /api/compliance/audit-log?level=all` |
+| **Format** | Timeline, grouped by day, human-readable verbs + icons | Dense paginaged table, 50/page |
+| **Filters** | Event type category | Action, severity, actor, date range |
+| **Export** | Not available | JSON export |
+| **Actor filter** | Not applicable | Filterable by actor |
+| **Events shown** | High-level actions only (allowlist) | All audit events |
+
+### High-Level Actions allowlist
+
+Defined in `src/lib/audit/highLevelActions.ts`. Controls which events appear in
+the Activity feed. The allowlist includes:
+
+- Provider add/remove/test events
+- Combo create/update/delete
+- API key lifecycle (create, revoke, rotate)
+- Budget threshold reached
+- Auth login/logout
+- Cloud agent session creation
+- MCP tool registration
+- Webhook create/delete
+- Quota pool/plan changes (`quota.*` actions, Group B)
+- Platform events (update, deploy)
+- Skill install/remove
+
+Events not in this list appear only in the Audit Log.
+
+### Adding a new high-level action
+
+Edit `src/lib/audit/highLevelActions.ts` and add the action string to
+`HIGH_LEVEL_ACTIONS`. This requires a PR (the list is code, not DB-configurable).
+The corresponding icon can be added to `src/lib/audit/activityIcons.ts`.
+
+---
+
+## Redirect: `/dashboard/logs/activity`
+
+The old path `/dashboard/logs/activity` is permanently redirected (HTTP 308) to
+`/dashboard/activity` via `permanentRedirect()` in
+`src/app/(dashboard)/dashboard/logs/activity/page.tsx`.
+
+The legacy sidebar ID `logs-activity` is preserved in `HIDEABLE_SIDEBAR_ITEM_IDS`
+(but removed from `SIDEBAR_DEFINITIONS`) to avoid breaking user presets that
+reference the old ID.
+
+---
+
+## i18n
+
+Namespaces added by Group B:
+
+| Namespace key | Covers |
+|---------------|--------|
+| `sidebar.costsSection` | Costs section label |
+| `sidebar.activity` | Activity sidebar item |
+| `sidebar.logsGroup` | Logs subgroup label |
+| `sidebar.systemGroup` | System subgroup label |
+| `sidebar.costsOverview` | Costs overview item |
+| `activity.*` | All Activity page strings (title, verbs, filters, empty state) |
+
+Source-of-truth locales: `pt-BR` and `en`. All other 39 locales fall back to
+English via the fallback mechanism (`src/i18n/fallback.ts` or `next-intl` fallback).