Struct UsageObservation 

pub struct UsageObservation {
    pub event_id: UsageEventId,
    pub subject: BillingSubject,
    pub meter_set: MeterSet,
    pub model_ref: ModelRef,
    pub provider_ref: Option<ProviderRef>,
    pub source: UsageSource,
    pub outcome: UsageOutcome,
    pub timing: UsageTiming,
    pub correlation: CorrelationIds,
    pub attributes: Attributes,
}

Raw usage observation - an immutable fact.

This is the primary input to the billing system. Once created, observations should never be modified - only rated to produce derived records.

Fields

event_id: UsageEventId

Unique identifier for this observation (idempotency key).

subject: BillingSubject

Who is being billed for this usage.

meter_set: MeterSet

The actual meter readings (token counts, image counts, etc.).

model_ref: ModelRef

Which model/pricing dimension this observation applies to.

provider_ref: Option<ProviderRef>

Which provider handled this request (if applicable).

source: UsageSource

Where this observation came from (provider API response, stream accumulation, etc.).

outcome: UsageOutcome

The final state of the request (success/error/timeout).

timing: UsageTiming

Timing information for this observation.

correlation: CorrelationIds

Correlation IDs for tracing across systems.

attributes: Attributes

Extensible attributes: is_fallback, step_type, estimated_reason, etc.

Trait Implementations

impl Clone for UsageObservation

fn clone(&self) -> UsageObservation

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for UsageObservation

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for UsageObservation

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Serialize for UsageObservation

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

where __S: Serializer,

Serialize this value into the given Serde serializer.