The APIs
Resend
Email delivery for explicitly opted-in monitoring digests to the owner's verified account address.
The facts a reader needs
| What it unlocks | Delivery of the weekly change summary email, only to an account that has turned it on and only to that account's verified address. No report reads it, and it is never called on signup or when you open a report. |
| When it is called | Only by the secret-protected notification dispatcher when sending is explicitly enabled and current verified-recipient consent is checked. Never on signup or preference reads. |
| Cost basis | Email account pricing and limits are separate from report-provider spend. No current allowance, delivery or fee is inferred from configuration. |
| Environment | RESEND_API_KEY |
| Bring your own key | Not on this deployment. |
A private durable outbox, exact payload/key retries and separate provider acceptance/delivery observation. No report acquisition uses this account.
Endpoints we call
| Endpoint | Why we call it |
|---|---|
POST emails | One send per queued summary, retried with the same key so a retry cannot duplicate a message. |
GET emails/{id} | Read-only delivery status, so the preferences page can say accepted, delivered or failed truthfully. |
Vercel AI Gateway
One door to every major language model — what GPT-5, Claude, Gemini, Grok and Perplexity each say about you — at each provider's own list price. WHICH models we actually route to, for what, at what rate, is src/local/model-registry.mjs; this row is the account, that file is the shelf.
Stripe
Hosted one-time credit-pack checkout and signed payment notifications for verified customer credit fulfillment.