Struct Usage 

pub struct Usage {
    pub prompt_tokens: u64,
    pub completion_tokens: u64,
    pub cached_tokens: u64,
    pub reasoning_tokens: u64,
}

Token usage as reported by the upstream’s usage object. cached_tokens is the subset of prompt_tokens served from the provider’s prompt cache; reasoning_tokens is the subset of completion_tokens spent on hidden reasoning. Both are carried separately so they can be priced (and metered) at their own rate rather than folded into the base input/output totals.

Fields

prompt_tokens: u64

completion_tokens: u64

cached_tokens: u64

Cached prompt tokens (⊆ prompt_tokens), from prompt_tokens_details.cached_tokens.

reasoning_tokens: u64

Reasoning completion tokens (⊆ completion_tokens), from completion_tokens_details.reasoning_tokens.

Implementations

impl Usage

pub fn total_tokens(&self) -> u64

Total tokens across prompt + completion (the budget’s Tokens unit basis).

Trait Implementations

impl Clone for Usage

fn clone(&self) -> Usage

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for Usage

impl Debug for Usage

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Usage

fn default() -> Usage

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for Usage

fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>

where D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Eq for Usage

impl PartialEq for Usage

fn eq(&self, other: &Usage) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl StructuralPartialEq for Usage