Pricing Model Updates

Token pricing is defined in src/models.rs. Built-in models are populated by populatedefaults() into the runtime model registry, and user/config models can be merged with initexternal_models().

Adding a New Model

1. Add a ModelInfo entry in populate_defaults() with:

- pricing: Use PricingStructure::Flat { inputper1m, outputper1m } for flat-rate models, or PricingStructure::Tiered for threshold-based pricing. - caching: Use the appropriate CachingSupport variant (None, OpenAI, Anthropic, OpenAIWithWrites, or Tiered). - servicetiers: Leave empty unless the provider has distinct priority/flex/batch rates. - datedpricing: Leave empty unless pricing changes by usage date. - isestimated: Set to true only when pricing is not confirmed by a provider/tool source. - inputtoken_semantics: Auto-derived for built-in models (defaults to ExcludesCache); only GPT/o-series models typically need IncludesCacheRead. External model configs should set this explicitly if it affects cache-read counting.

1. If the model has aliases (date suffixes, provider-prefixed names, regional names, etc.), add entries to the alias section mapping each observed name to the canonical model name.
2. Add or update tests in src/models.rs for canonical pricing, aliases, caching, and estimated/non-estimated status.

Dated Pricing Overrides

Use dated_pricing when a model has temporary promotional pricing, launch pricing, or another time-bounded rate that should apply based on the original usage timestamp.

The default pricing and caching fields should represent the durable/current sticker price. Each DatedPricing override has a validuntil: NaiveDate exclusive end date and applies when usagedate < validuntil. For example, an introductory rate that applies through 2026-08-31 should use validuntil = NaiveDate::fromymdopt(2026, 9, 1).expect("valid date").

When adding a dated override:

• Keep the model's default pricing/caching at the post-promo or durable rate.
• Add the temporary rate with adddatedpricing!() after add_model!().
• Add boundary tests for the final day of the temporary rate and the first day after it ends.
• Prefer dated calculator functions in analyzers that know the usage timestamp.

Price Calculation

Use models::calculatetotalcostforservicetierat() when an analyzer has a message or event timestamp. This preserves historical costs across dated pricing windows.

Use the undated compatibility helpers, such as models::calculatetotalcost(), only for tests, config-like calculations, or call sites that truly do not know the usage date. Undated helpers use the model's default pricing/caching, not temporary dated overrides.

Common Pricing Sources

• Anthropic pricing
• OpenAI pricing
• Google AI pricing