Struct Event 

pub struct Event {

    pub timestamp: String,
    pub event: String,
    pub model_id: String,
    pub request_kind: String,
    pub stream: bool,
    pub status: String,
    pub latency_ms: u64,
    pub input_tokens: u64,
    pub output_tokens: u64,
    pub estimated_cost_usd: f64,
    pub tool_call_count: u64,
    pub cache_status: String,
    pub trace_id: String,
}

One structured observability event, serialized as a single snake_case JSON line.

Deliberately metadata-only: it has no field for prompt content or tool output, so a plain Event can never carry user text to disk.

Fields

timestamp: String

RFC 3339 UTC timestamp, e.g. 2026-09-10T12:00:00Z.

event: String

Event kind, e.g. chat_completion, catalog_fetch.

model_id: String

Model identifier, e.g. @cf/deepseek-ai/deepseek-v4-flash-0731.

request_kind: String

Request surface, e.g. chat_completions.

stream: bool

Whether the request used streaming.

status: String

Final status, e.g. an HTTP status code string.

latency_ms: u64

Total request latency in milliseconds.

input_tokens: u64

Reported input/prompt tokens.

output_tokens: u64

Reported output/completion tokens.

estimated_cost_usd: f64

Estimated request cost in USD.

tool_call_count: u64

Number of tool calls issued during the request.

cache_status: String

Cache disposition, e.g. miss, hit, or empty when unknown.

trace_id: String

Opaque correlation id tying related events together.

Trait Implementations

impl Clone for Event

fn clone(&self) -> Event

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for Event

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for Event

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

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl PartialEq for Event

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

Equality operator ==.

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

Inequality operator !=.

impl Serialize for Event

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

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for Event