Grow your Mailchimp audience with real Business Central customers

**Objective:** Add Business Central customers who are not yet in the Mailchimp audience `{list-name}` to it, with the subscription status `{status}` (default pending, which sends Mailchimp's double opt-in confirmation). Limit the customers to salesperson `{salesperson-code}` if given. Use the Business Central company `{company}`; if it is empty, omit the `company` filter.

**Step 1: Find the audience**

Call `mailchimp-get-list` with `name` set to `{list-name}`. If it does not return exactly one list, list what it found and stop. Take its list-id.

**Step 2: Business Central customers**

Call `business-central-get-customer`, with `salesperson-code` set if one was given. Drop customers with an empty email and customers whose blocked value is anything other than blank or none.

**Step 3: Who is missing from the audience**

For each remaining email, call `mailchimp-get-list-member` with `email` set to it and `list-name` set to `{list-name}`. Skip anyone already present, whatever their status. Never re-add someone whose status is unsubscribed or cleaned.

**Step 4: Confirm**

Show a table of the customers to be added (customer-number, name, email) and the status they will get, with the count. Ask the user to confirm. Do not continue without an explicit yes.

**Step 5: Add and confirm**

For each confirmed customer, call `mailchimp-add-list-member` once with `list-id`, `email-address` and `status`. Leave first-name and last-name blank, because a Business Central customer name is often a company name. Then call `mailchimp-get-list-member` again for each email and report which adds are confirmed and which failed, with the error.

**Rules & Guidelines:**

* `mailchimp-get-list`, `mailchimp-get-list-member` and `mailchimp-add-list-member` are on the mailchimp server. `business-central-get-customer` is on the business-central server.
* `mailchimp-add-list-member` is the only write this prompt may make, once per confirmed email. Do NOT call `mailchimp-update-list-member` and do NOT call any business-central create or update tool.
* Only use status subscribed if the user states the customers have given marketing consent. Otherwise use pending.

**Validation:**

* If no customers are missing from the audience, say so and stop before Step 4.
* If more than 100 customers would be added, add the first 100 after confirmation and report the remainder.
* Match emails case-insensitively after trimming spaces.