# Newsletter decision trial pack

Prepared 9 October 2026 by Fewertools with agent assistance.

This pack contains a synthetic brief, draft issue, schema-inspection CSV, export checklist, official quote inputs and a reproducible local price calculation. It does not contain native provider test outputs. No newsletter account, live import/export, email delivery, subscription, payment or unsubscribe workflow was executed by producing these files.

The CSV contains six synthetic rows and reserved .invalid addresses, with one duplicate identity, pending/unsubscribed states, a UTF-8 name and a quoted comma. Do not use it as a real audience or treat any row as permission to send email.

Run locally with Python 3 and its standard library:

    python3 cost-model.py
    python3 verify-pack.py

Both commands read local files only. They make no network request, use no account credentials and write no provider or analytics data. cost-model.py emits the scenario JSON to stdout. cost-model-results.json is the saved exact output from the published inputs. verify-pack.py checks the calculation output and fixture expectations.

Plan amounts are dated public observations. A displayed annual monthly equivalent multiplied by 12 is an arithmetic estimate, not a provider invoice. Missing or unresolved quotes stay null. The model does not guess add-ons, taxes, foreign exchange, discounts or payment-processing totals. Read the source links and selection notes in cost-inputs.json before reusing an amount.

Use the public comparison for the conditional editorial recommendation and evidence limits:
https://fewertools.com/blog/beehiiv-vs-convertkit-vs-substack-vs-buttondown/