Duplicate Customer Finder

Purpose

Scan WooCommerce customer records for duplicates: same billing email across multiple accounts, or identical shipping address across different email addresses. Exports a conflict report with customer IDs for manual review and CRM deduplication. Read-only.

Prerequisites

• WooCommerce store with REST API enabled
• Consumer Key with Read scope
• Minimum WooCommerce version: 3.5.0

Parameters

Authentication

WooCommerce uses OAuth 1.0a for HTTP and Basic Auth over HTTPS.

For HTTPS stores (recommended):

Authorization: Basic base64(consumer_key:consumer_secret)

For HTTP stores (development only): Use OAuth 1.0a — include oauth_consumer_key, oauth_nonce, oauth_signature, oauth_signature_method=HMAC-SHA1, oauth_timestamp, oauth_version=1.0

Never log or output consumer_key or consumer_secret values.

See docs/AUTHENTICATION.md for full setup instructions.

Safety

Read-only skill — no mutations are executed. Safe to run at any time.

Workflow Steps

Step 1 — Fetch all customers

GET /wp-json/wc/v3/customers?per_page=100&page=1

Extract: id, email, billing.email, billing.address_1, billing.city, billing.postcode, billing.country

Step 2 — Build lookup maps

• Email map: normalized_email → [customer_ids]
• Address map: normalized_address_fingerprint → [customer_ids] (fingerprint = lowercased address_1 + postcode + country)

Step 3 — Find conflicts

Email duplicates: map entries with > 1 customer ID. Address duplicates: map entries with > 1 customer ID across different emails.

Step 4 — Export

API Endpoints Used

GET  /wp-json/wc/v3/customers   — all customer records

Pagination Strategy

WooCommerce REST API uses page/per_page pagination (not cursor-based).

Standard pattern:

page = 1
while True:
  response = GET /endpoint?per_page=100&page=page
  process(response)
  if len(response) < 100: break
  page += 1

Maximum per_page is 100 for most endpoints. The X-WP-Total and X-WP-TotalPages response headers report totals. Always read X-WP-TotalPages on the first request to estimate job size.

Session Tracking

Claude MUST emit the following output at each stage. This is mandatory.

STARTUP:

╔══════════════════════════════════════════╗
║  SKILL: woo-duplicate-customer-finder    ║
║  STORE: <store_url>                      ║
║  TIME:  <ISO-8601 UTC>                   ║
║  MODE:  READ-ONLY                        ║
╚══════════════════════════════════════════╝

PER-OPERATION (emit after each API call batch):

[N/TOTAL] <METHOD> <endpoint> → <result_count> records | params: <key>=<val>

COMPLETION (human format):

╔══════════════════════════════════════════╗
║  COMPLETE: woo-duplicate-customer-finder ║
║  RECORDS PROCESSED: <n>                  ║
║  OUTPUT: <filename>                      ║
╚══════════════════════════════════════════╝

COMPLETION (json format):

{
  "skill": "woo-duplicate-customer-finder",
  "store": "<store_url>",
  "completed_at": "<ISO-8601>",
  "records_processed": <n>,
  "output_file": "<path>",
  "dry_run": false
}

Output Format

CSV filename: woo-duplicate-customer-finder_<YYYY-MM-DD>.csv Columns: match_type, match_value, customer_ids, emails, names, order_counts, total_spends

Error Handling

Best Practices

• Email matching catches the most common duplicates; address matching catches the same household with different emails.
• Do not delete duplicate accounts without reviewing order history on each — manually merge order counts first.
• Run after every large customer import to catch duplicates introduced by the import.