# Market Backend Metrics CSV Implementation Plan

> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.

**Goal:** Extend CSV export so it appends the six backend metrics already stored on each market record.

**Architecture:** Keep the existing export flow intact and modify only the CSV column definition layer. Reuse `MarketRecord.backendMetrics` as the sole source for the six new CSV columns so the exported data matches what the plugin already loaded into memory.

**Tech Stack:** TypeScript, existing market CSV exporter, Vitest

---

## File Map

- Modify: `src/content/market/csv-exporter.ts`
  - Append six backend metrics columns after existing CSV columns.
- Modify: `tests/csv-exporter.test.ts`
  - Add failing tests for backend metric headers and values.

### Task 1: Backend Metrics CSV Columns

**Files:**
- Modify: `tests/csv-exporter.test.ts`
- Modify: `src/content/market/csv-exporter.ts`

- [ ] **Step 1: Write the failing CSV exporter tests**

Add tests for:
- the six backend metric headers appended after current columns
- backend metric values exported from `record.backendMetrics`
- blank cells when `backendMetrics` is absent

- [ ] **Step 2: Run test to verify it fails**

Run: `npm test -- tests/csv-exporter.test.ts`
Expected: FAIL because the exporter does not include backend metric columns yet.

- [ ] **Step 3: Write the minimal exporter change**

Append these six columns:
- `看后搜率`
- `看后搜数`
- `新增A3数`
- `新增A3率`
- `CPA3`
- `cp_search`

Each column reads from:
- `record.backendMetrics?.afterViewSearchRate`
- `record.backendMetrics?.afterViewSearchCount`
- `record.backendMetrics?.a3IncreaseCount`
- `record.backendMetrics?.newA3Rate`
- `record.backendMetrics?.cpa3`
- `record.backendMetrics?.cpSearch`

- [ ] **Step 4: Run test to verify it passes**

Run: `npm test -- tests/csv-exporter.test.ts`
Expected: PASS

- [ ] **Step 5: Run full verification**

Run:

```bash
npm test
npm run build
```

Expected:
- full test suite passes
- build succeeds

- [ ] **Step 6: Commit**

```bash
git add src/content/market/csv-exporter.ts tests/csv-exporter.test.ts docs/superpowers/specs/2026-04-22-market-backend-metrics-csv-design.md docs/superpowers/plans/2026-04-22-market-backend-metrics-csv.md
git commit -m "feat: export backend metrics in csv"
```