Usage-metered payments

Use usage-metered pricing when the API naturally charges by a measured unit.

Agent summary

• Use the unit that matches the provider's cost driver.
• Make scale explicit.
• Use tiers when larger usage should have a different unit price.
• Keep endpoint descriptions concrete enough for agents to choose correctly.

Example

metering:
  dimensions:
    - direction: usage
      unit: characters
      scale: 1000
      tiers:
        - price_usd: 0.01

Good units include requests, tokens, characters, minutes, pages, and bytes when they match the API behavior.