Struct UsageInfo 

pub struct UsageInfo {
    pub prompt_tokens: Option<u32>,
    pub completion_tokens: Option<u32>,
    pub total_tokens: Option<u32>,
    pub reasoning_tokens: Option<u32>,
}

Token usage information for an LLM call.

Fields

prompt_tokens: Option<u32>

completion_tokens: Option<u32>

total_tokens: Option<u32>

reasoning_tokens: Option<u32>

Tokens used for reasoning / thinking (DeepSeek, OpenAI o-series, etc.). Always None on the Anthropic protocol: its usage object has no thinking breakdown — thinking tokens are folded into completion_tokens.

Implementations

impl UsageInfo

pub fn merge(&mut self, other: &UsageInfo)

Merge a partial usage event into self; the incoming Some field wins over the existing value, a None leaves it untouched.

Streaming protocols may split usage across several events (Anthropic sends prompt_tokens in message_start and the final completion_tokens in message_delta). Replacing the whole struct on each event would silently zero out fields the last event omits, so consumers must fold events with this method instead.

Trait Implementations

impl Clone for UsageInfo

fn clone(&self) -> UsageInfo

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for UsageInfo

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

Formats the value using the given formatter.

impl Default for UsageInfo

fn default() -> UsageInfo

Returns the “default value” for a type.