A budget per player

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Every answer has a price

Theo opens the Garden Guide's first full bill. AI services charge per token, a few letters of text. Shard Garden pays for the tokens it sends (the prompt) and the tokens it gets back (the answer).

Real prices

Anthropic lists Claude Haiku 5.5 at "$0.10 / MTok" for input and "$0.50 / MTok" for output: US$0.10 per million tokens sent and US$0.50 per million received. Cached input costs US$0.01 per million.

Do the math

one question
Prompt: 5,500 tokens  at US$0.10 a millionAnswer: 400 tokens  at US$0.50 a million

What does one question cost?

  1. US$0.00075
  2. US$0.0075
  3. US$0.075
Show the answer

US$0.00075

5,500 × 0.10 ÷ 1,000,000 = 0.00055, plus 400 × 0.50 ÷ 1,000,000 = 0.0002.

Tiny costs, big numbers

US$0.00075 looks like nothing. A million players asking 10 questions a day is 10 million questions: US$7,500 a day.

A budget per player

Kai asks the founder's question: can the studio afford it? An average Shard Garden player brings in about US$0.40 a month, the studio's revenue per player. Kai and Theo decide AI may take at most a quarter of that: US$0.10 a player a month. Spend more, and each new player costs more to serve than the studio can keep. A daily question limit holds every player inside it.

Quick check

Theo sets a limit for each player, not just a total. Why?

  1. So one player asking thousands of questions can't use up everyone's budget
  2. Because totals can't be measured
  3. To make players ask less
Show the answer

So one player asking thousands of questions can't use up everyone's budget

A total can be spent by a few players, or by a script. A limit per player keeps it fair.

Batch what can wait

Anthropic's Batch API offers "a 50% discount on both input and output tokens" for requests that can wait. Shard Garden writes each player's weekly garden tips this way, not in real time.

Quick check

Every AI request must be answered in real time.

Show the answer

False

Work that can wait, like weekly tips, costs half as much in a batch.

Watch the bill daily

A cost dashboard shows spending per day and per feature, with an alert when a day costs twice the usual. A bug that repeats a request can spend a month's budget in hours.

Set the budget yourself

Four plans for the Garden Guide. One gives players the most questions within budget.

Bolt says: Next: set the budget.

Fact-checked 12 October 2026