Graphorin API reference v0.15.1

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Graphorin API reference / @graphorin/provider / / WithCostTrackingOptions

Interface: WithCostTrackingOptions

Defined in: packages/provider/src/middleware/with-cost-tracking.ts:97

Stable

Options for withCostTracking.

Properties

Property	Modifier	Type	Description	Defined in
onUsage?	readonly	(info) => void	Hook fired on every finish event with the parsed usage. The hook receives the underlying provider's name + modelId so the caller can route into a per-model accumulator.	packages/provider/src/middleware/with-cost-tracking.ts:103
priceLookup?	readonly	(info) => | { cachedReadPerMtok?: number; cacheWritePerMtok?: number; inputPerMtok?: number; outputPerMtok?: number; } | null	Optional pricing lookup. When set, the middleware computes costUsd from the returned price and surfaces it on the hook. cachedReadPerMtok / cacheWritePerMtok price the prompt-cache legs; when omitted, cache tokens are billed at the full input rate. For reads that over-counts (reads are discounted), but for writes it can UNDER-count: providers with a write premium (Anthropic, and OpenAI from GPT-5.6 on) charge 1.25x input for cache writes, so keep the write rate populated for models that report cacheWriteTokens.	packages/provider/src/middleware/with-cost-tracking.ts:125