Email Deliverability Audit — Shopify Admin Skills

Read-only: scans the customer database for malformed emails, role accounts, disposable domains, and bounce-suspect patterns to protect sender reputation.

Purpose

Scans the entire customer list and flags addresses that will hurt email deliverability if included in marketing sends: syntactically invalid addresses, role accounts (info@, admin@, sales@), known disposable / temporary domains, and suspected hard-bounce patterns. Output is a suppression list ready to import into your email platform. Read-only — no mutations.

Prerequisites

Authenticated Shopify CLI session: shopify store auth --store --scopes read_customers

API scopes: read_customers

Parameters

Parameter	Type	Required	Default	Description
store	string	yes	—	Store domain (e.g., mystore.myshopify.com)
marketing_consent_only	bool	no	true	Only scan customers who currently accept marketing — those are the ones at risk of being mailed
disposable_domains	array	no	built-in list	Override built-in disposable-domain list
role_localparts	array	no	`["info","admin","sales","support","contact","noreply","help","webmaster","postmaster"]`	Local-part prefixes to flag as role accounts
format	string	no	human	Output format: `human` or `json`

Safety

> ℹ️ Read-only skill — no mutations are executed. Safe to run at any time. No emails are sent, no marketing consent is changed.

Detection Rules

For each customer email, run these checks in order and assign one or more flags:

invalid_syntax — fails RFC 5322 local-part / domain validation, missing @, contains whitespace, double dots, leading/trailing dot

role_account — local part exactly matches a role_localparts entry (case-insensitive)

disposable_domain — domain matches the disposable-domain list (mailinator, guerrillamail, tempmail-style domains, etc.)

plus_alias — contains + in local part (informational; not a deliverability problem on its own, but useful for de-duplication)

bounce_suspect — heuristics: numeric-only local part, length > 64 chars, ALL-CAPS, repeated characters (aaaaa), keyboard rolls (asdfghjk)

duplicate — same normalized email already seen in the customer set

A customer can carry multiple flags; the most severe (invalid_syntax > bounce_suspect > disposable_domain > role_account > plus_alias) drives the recommended action.

Workflow Steps

OPERATION: customers — query

Inputs: first: 250, select id, defaultEmailAddress { emailAddress, marketingState }, numberOfOrders, tags, pagination cursor. If marketing_consent_only: true, filter query: "email_marketing_state:subscribed"

Expected output: All targeted customers with email; paginate until hasNextPage: false

Run detection rules over each email; collect flags

Aggregate counts per flag, build suppression list

GraphQL Operations

# customers:query — validated against api_version 2025-01
query DeliverabilityAudit($query: String, $after: String) {
  customers(first: 250, after: $after, query: $query) {
    edges {
      node {
        id
        displayName
        defaultEmailAddress {
          emailAddress
          marketingState
        }
        numberOfOrders
        amountSpent {
          amount
          currencyCode
        }
        tags
        createdAt
      }
    }
    pageInfo {
      hasNextPage
      endCursor
    }
  }
}

Session Tracking

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

On start, emit:

╔══════════════════════════════════════════════╗
║  SKILL: Email Deliverability Audit           ║
║  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>

On completion, emit:

For format: human (default):

══════════════════════════════════════════════
EMAIL DELIVERABILITY AUDIT
  Customers scanned:       <n>
  Subscribed customers:    <n>
  ─────────────────────────────
  Invalid syntax:          <n> (<pct>%)   🔴 suppress
  Role accounts:           <n> (<pct>%)   ⚠️ suppress
  Disposable domains:      <n> (<pct>%)   ⚠️ suppress
  Bounce-suspect patterns: <n> (<pct>%)   ⚠️ review
  Plus aliases:            <n> (<pct>%)   ℹ️ informational
  Duplicates:              <n> (<pct>%)   ℹ️ informational

  Recommended suppression: <n>  (<pct>% of subscribed)
  Output: deliverability_audit_<date>.csv
══════════════════════════════════════════════

For format: json, emit:

{
  "skill": "email-deliverability-audit",
  "store": "<domain>",
  "customers_scanned": 0,
  "flags": {
    "invalid_syntax": 0,
    "role_account": 0,
    "disposable_domain": 0,
    "bounce_suspect": 0,
    "plus_alias": 0,
    "duplicate": 0
  },
  "recommended_suppressions": 0,
  "output_file": "deliverability_audit_<date>.csv"
}

Output Format

CSV file deliverability_audit_.csv with columns:

customer_id, email, flags, recommended_action, marketing_state, order_count, total_spent, created_at

recommended_action is one of: suppress, review, keep.

Error Handling

Error	Cause	Recovery
`THROTTLED`	API rate limit exceeded	Wait 2 seconds, retry up to 3 times
Customer with no email	Phone-only / POS account	Skip, do not include in suppression list
Disposable list out of date	New temp-mail domain not in built-in list	Caller can override via `disposable_domains` parameter
Unicode local parts	Internationalized email addresses	Normalize via NFC; do not flag valid IDN domains

Best Practices

Run before every large promotional send — high invalid / bounce rates above 2% put your sending domain reputation at risk.

Treat role_account flags as soft-suppression: those addresses rarely consent to marketing meaningfully and frequently mark mail as spam.

Re-audit quarterly even if the customer list is static — domain reputation lists change, and disposable-email providers add new domains.

Pair with marketing-consent-report to confirm consent state aligns with what your email service provider has on file.

Hand the resulting suppression CSV to your email service provider's import-suppression-list feature; do not silently delete customers from Shopify based on this audit.