Struct Usage 

pub struct Usage {
    pub prompt_tokens: Option<u64>,
    pub completion_tokens: Option<u64>,
    pub total_tokens: Option<u64>,
    pub cache_read_tokens: Option<u64>,
    pub cache_write_tokens: Option<u64>,
    pub cost: Option<CostEstimate>,
}

Token usage statistics from an LLM API response.

All fields are Option<u64> because not every provider supplies every field. For example, cache token counts are only available from providers that support prompt caching.

Fields

prompt_tokens: Option<u64>

Tokens consumed by the prompt/input.

completion_tokens: Option<u64>

Tokens generated in the completion/output.

total_tokens: Option<u64>

Total tokens (prompt + completion).

cache_read_tokens: Option<u64>

Tokens served from prompt cache (read).

cache_write_tokens: Option<u64>

Tokens written to prompt cache.

cost: Option<CostEstimate>

Optional cost reported by provider data or estimated from Relay model pricing.

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 Debug for Usage

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

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<Usage, <__D as Deserializer<'de>>::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for Usage

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

Equality operator ==.

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

Inequality operator !=.

impl Serialize for Usage

fn serialize<__S>( &self, __serializer: __S, ) -> Result<<__S as Serializer>::Ok, <__S as Serializer>::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Usage