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Part 6 of 7 · Daily briefing bot series ~3 min read

What the briefing bot costs

A small daily digest doesn’t have to cost real money. Most of the system runs on free tiers; the only meaningful spend is the AI for ranking, and even that’s pennies. Here’s where the dollars actually go.

Anatomy of a typical monthly bill: three tiers and a total Three columns side by side, each labeled at the top. The left column, “Always free”, lists Lambda runs, EventBridge timer, Lambda Function URLs (webhook endpoints), SQS and SNS, and DynamoDB for small tables — each with a cost of zero. The middle column, “Tiny fixed cost”, lists S3 storage at pennies per month and Secrets Manager at about 40 cents per secret per month. The right column, “Grows with use”, lists cheap embeddings at pennies per month, the smart AI judge at cents up to about a dollar per month, and Amazon SES email sends at fractions of a cent per month for daily delivery. Below all three columns, a wide total bar reads: total, about one to three dollars per month for a typical setup. Bottom note: a coffee a month, possibly less. The bot only spends when it’s actively reading and ranking. Where the dollars go in a typical month Always free $0 Lambda runs free Morning timer free Webhook URLs free Queues, alerts free Small tables free all under the perpetual free tier Tiny fixed cost ~ $0.50/mo S3 storage cents Password vault ~$0.40 each flat, regardless of activity Grows with use ~ $0.50–$2.00/mo Cheap embeddings pennies Smart AI (judge) cents to ~$1 Email send (SES) <1¢/mo scales with how loud the news is Total, typical month about $1–$3 / month budget alarm at $5 catches anything weird before it grows A coffee a month, possibly less. The bot only spends when it’s actively reading and ranking.
Fig 6. Three tiers of cost: free, tiny fixed, variable. Most of the bill is the variable column — and that column is still pennies on a quiet news week.

Free at this scale

  • The robots — the cloud gives you a million function runs a month for free. The bot uses a tiny fraction of that.
  • The morning timer — 14 million wake-ups a month free. The bot needs 30.
  • Queues and alerts — the small bookkeeping pieces are all on free tiers at this volume.
  • Small tables — the small lists the bot keeps (which items it’s already seen, which digests it’s sent) fit comfortably in the always-free tier.

Costs pennies to a dollar each month

  • Storage — the raw items, today’s digest, the config files. Cents per month.
  • Password vault — about 40 cents a month for each secret you store (any access keys for the sources you watch).

Grows with how busy your sources are

  • Quick scoring — the small AI looks at each item for about a fraction of a cent. A heavy news day with 200 items still rounds to pennies.
  • Smart AI for borderline ranking — about a tenth of a cent per call. Only borderline items get this treatment, so it’s usually a handful per day. A few cents to a dollar a month.
  • Email delivery — about a tenth of a cent per send (priced per thousand messages). A daily digest is fractions of a cent per month.

Three traps you’re avoiding

  • No always-on server — that alone would be $30+ a month before doing anything.
  • No managed scraper service — the page worker is a small bit of code that runs only when there’s something to fetch. Managed scraping services charge per page and add up fast.
  • No infinite logs — 7-day retention; logs can’t pile into a slow-growing surprise bill.

In plain words

A coffee a month, possibly less. The bot only spends money when it’s actively reading and ranking; the rest of the day it costs nothing. Set a budget alarm at $5 a month and you’ll know within a day if anything weird ever starts to happen.

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