Customer Merge

Merges duplicate customer records: invokes Shopify's native customer merge API where supported, otherwise consolidates the loser record's tags and notes into the winner via customerUpdate.

shopify-admin-customer-merge


Purpose

Resolves duplicate customer records identified by duplicate-customer-finder. Where the Shopify Admin API exposes customerMerge (a native merge that moves orders, addresses, subscriptions, and metafields onto a winner record), this skill calls it directly. When customerMerge is unavailable or fails for the given account pair, the skill falls back to consolidating searchable metadata — tags, notes, marketing consent — onto the winner via customerUpdate, then writes a clear annotation to the loser record so staff can complete the merge manually in Shopify Admin.


Prerequisites

  • Authenticated Shopify CLI session: shopify store auth --store --scopes read_customers,write_customers
  • API scopes: read_customers, write_customers

  • Parameters


    ParameterTypeRequiredDefaultDescription
    storestringyesStore domain (e.g., mystore.myshopify.com)
    formatstringnohumanOutput format: human or json
    dry_runboolnotruePreview merge plan without executing mutations
    customer_winner_idstringyesGID of the customer record to keep (e.g., gid://shopify/Customer/12345)
    customer_loser_idstringyesGID of the customer record to merge into the winner
    use_native_mergeboolnotrueTry customerMerge first; if it fails or is unavailable, fall back to consolidation via customerUpdate
    merge_tagsboolnotrueUnion the loser's tags onto the winner
    merge_noteboolnotrueAppend the loser's note to the winner (with timestamp prefix)
    annotate_loserboolnotrueWrite a note on the loser record pointing to the winner GID for manual cleanup

    Safety


    > ⚠️ Steps 2–4 execute mutations that modify customer records. customerMerge is irreversible — once orders and addresses are moved to the winner, the loser record is closed and cannot be split back. Run with dry_run: true first to confirm winner/loser GIDs and the merge plan. The default is dry_run: true. Always verify both records belong to the same human (matching email, phone, name) using duplicate-customer-finder output before committing. Do not merge a customer with active subscriptions or unfulfilled orders without confirming downstream systems will follow the new owner GID.


    Workflow Steps


  • OPERATION: customer — query (called twice: winner and loser)
  • Inputs: id: , select id, displayName, firstName, lastName, defaultEmailAddress { emailAddress }, phone, tags, note, numberOfOrders, amountSpent, emailMarketingConsent { marketingState }, smsMarketingConsent { marketingState }, addresses(first: 25) { id }, createdAt

    Expected output: Both records' full identity payload — abort if either GID does not resolve


  • OPERATION: customerMerge — mutation (only if use_native_merge: true and not dry_run)
  • Inputs: customerOneId: , customerTwoId: , overrideFields: prefer winner's name/email/phone/locale/marketing-consent

    Expected output: job.id (merge runs asynchronously), userErrors. If userErrors indicates merge is not supported for this pair (B2B, gift card holder, subscriber, etc.), proceed to step 3 fallback.


  • OPERATION: customerUpdate — mutation (winner) — fallback path or when use_native_merge: false
  • Inputs: input.id: , input.tags: (only if merge_tags), input.note: :\n" + loser.note> (only if merge_note)

    Expected output: customer.id, customer.tags, customer.note, userErrors


  • OPERATION: customerUpdate — mutation (loser) — only if annotate_loser: true
  • Inputs: input.id: , input.note: "\n[YYYY-MM-DD] DUPLICATE — merge target: . Manually close in Shopify Admin once orders are reviewed.", input.tags:

    Expected output: customer.id, customer.tags, customer.note, userErrors


    GraphQL Operations


    # customer:query — validated against api_version 2025-01
    query CustomerForMerge($id: ID!) {
      customer(id: $id) {
        id
        displayName
        firstName
        lastName
        defaultEmailAddress { emailAddress }
        phone
        tags
        note
        numberOfOrders
        amountSpent { amount currencyCode }
        emailMarketingConsent { marketingState marketingOptInLevel consentUpdatedAt }
        smsMarketingConsent { marketingState marketingOptInLevel consentUpdatedAt }
        addresses(first: 25) { id address1 city provinceCode countryCodeV2 zip }
        createdAt
      }
    }
    

    # customerMerge:mutation — validated against api_version 2025-01
    mutation CustomerMerge(
      $customerOneId: ID!
      $customerTwoId: ID!
      $overrideFields: CustomerMergeOverrideFields
    ) {
      customerMerge(
        customerOneId: $customerOneId
        customerTwoId: $customerTwoId
        overrideFields: $overrideFields
      ) {
        job { id done }
        resultingCustomerId
        userErrors { field message code }
      }
    }
    

    # customerUpdate:mutation — validated against api_version 2025-01
    mutation CustomerConsolidate($input: CustomerInput!) {
      customerUpdate(input: $input) {
        customer { id displayName tags note }
        userErrors { field message }
      }
    }
    

    Session Tracking


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


    On start, emit:

    ╔══════════════════════════════════════════════╗
    ║  SKILL: Customer Merge                       ║
    ║  Store: <store domain>                       ║
    ║  Started: <YYYY-MM-DD HH:MM UTC>             ║
    ╚══════════════════════════════════════════════╝
    

    After each step, emit:

    [N/TOTAL] <QUERY|MUTATION>  <OperationName>
              → Params: <brief summary of key inputs>
              → Result: <count or outcome>
    

    If dry_run: true, prefix every mutation step with [DRY RUN] and do not execute it.


    On completion, emit:


    For format: human (default):

    ══════════════════════════════════════════════
    CUSTOMER MERGE OUTCOME
      Winner:           <name> (<email>)  Orders: <n>  Spent: $<n>
      Loser:            <name> (<email>)  Orders: <n>  Spent: $<n>
      Path used:        <native|fallback|skipped>
      Merge job:        <id or "n/a">
      Tags consolidated: <n>
      Note appended:    <yes/no>
      Loser annotated:  <yes/no>
      Errors:           <n>
      Output:           none
    ══════════════════════════════════════════════
    

    For format: json, emit:

    {
      "skill": "customer-merge",
      "store": "<domain>",
      "started_at": "<ISO8601>",
      "completed_at": "<ISO8601>",
      "dry_run": true,
      "winner_id": "<gid>",
      "loser_id": "<gid>",
      "outcome": {
        "path": "native|fallback",
        "merge_job_id": "<id or null>",
        "resulting_customer_id": "<gid or null>",
        "tags_consolidated": 0,
        "note_appended": false,
        "loser_annotated": false,
        "errors": 0,
        "output_file": null
      }
    }
    

    Output Format

    No CSV output. The session summary reports the merge job ID, the resulting customer GID, and which path was taken. For batch merges, run this skill once per pair and capture the JSON output.


    Error Handling

    ErrorCauseRecovery
    THROTTLEDAPI rate limit exceededWait 2 seconds, retry up to 3 times
    customerMerge userError: customer has subscriptionsActive subscription on loserCancel subscription before merge or use fallback path
    customerMerge userError: B2B customerCompany-affiliated recordUse fallback path; manual merge in Shopify Admin
    customerMerge userError: gift card holderLoser owns gift card balanceTransfer gift card or use fallback path
    Either GID not foundWrong ID or deleted customerRe-run duplicate-customer-finder
    Merge job pendingAsync merge not yet completeRe-query Job(id) to confirm done: true

    Best Practices

  • Always run duplicate-customer-finder first to confirm the pair is genuinely duplicate. Manual misclassifications are unrecoverable.
  • Pick the winner deliberately: typically the record with more orders, the verified email, or the older createdAt. Avoid making the marketing-consenting record the loser.
  • Run dry_run: true first; the preview shows both records' order counts and spend so you can sanity-check before committing.
  • For large dedup runs, write a wrapper script that calls this skill once per pair and feeds it from duplicate-customer-finder's CSV output — never batch merges in a single call.
  • After native merge, the job.done: false response is normal — Shopify processes merges asynchronously. Re-query the job ID until completion before assuming the loser is closed.
  • The fallback path (customerUpdate consolidation only) does not move orders. It preserves searchability via tags/notes so a human can finish the merge in Shopify Admin (Customers → Merge).