> This page is for NeMo Relay, version dev.
> For other versions, use one of these documentation indexes:
> - Latest (v0.11.1) (default): https://docs.nvidia.com/nemo/relay/latest/llms.txt
> - dev: https://docs.nvidia.com/nemo/relay/dev/llms.txt
> - v0.11.1: https://docs.nvidia.com/nemo/relay/v0.11.1/llms.txt
> - v0.10.4: https://docs.nvidia.com/nemo/relay/v0.10.4/llms.txt
> - v0.9.4: https://docs.nvidia.com/nemo/relay/v0.9.4/llms.txt
> - v0.8.4: https://docs.nvidia.com/nemo/relay/v0.8.4/llms.txt
> - v0.7.3: https://docs.nvidia.com/nemo/relay/v0.7.3/llms.txt

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# Struct Event View

> API documentation for the Rust `EventView` struct in crate `nemo_relay_observability`.

Generated from `cargo doc --no-deps -p nemo-relay-builtins -p nemo-relay-diagnostics -p nemo-relay-logging -p nemo-relay-plugin-host -p nemo-relay-codecs -p nemo-relay -p nemo-relay-runtime -p nemo-relay-model-pricing -p nemo-relay-resource-metrics -p nemo-relay-observability -p nemo-relay-adaptive -p nemo-relay-pii-redaction -p nemo-relay-ffi -p nemo-relay-types -p nemo-relay-plugin -p nemo-relay-worker-proto -p nemo-relay-worker`.

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## Fields

### `event: &'a Event`

### `host: &'a dyn ObservabilityHost`

## Implementations

### `impl<'a> EventView<'a>`

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#### `new`

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#### `as_event`

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#### `normalized_llm_request`

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#### `normalized_llm_response`

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## Methods from Deref \<Target = Event>

#### `kind`

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Return the ATOF event kind.

##### Returns

`"scope"` for \[`Event::Scope`] and `"mark"` for \[`Event::Mark`].

#### `try_to_json_value`

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Try to return this event as the canonical JSON object delivered by language bindings to subscriber callbacks and ATOF exporters.

#### `to_json_value`

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Return this event as the canonical JSON object delivered by language bindings to subscriber callbacks.

#### `to_json_string`

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Return this event as canonical JSON.

#### `scope_category`

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Return the lifecycle phase for scope events.

##### Returns

`Some` lifecycle phase for scope events, otherwise `None`.

#### `category`

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Return the semantic category if present.

##### Returns

`Some` category for scope events and categorized mark events, otherwise `None`.

#### `category_profile`

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Return the category-specific profile if present.

##### Returns

`Some` profile when category-specific fields are present.

#### `tool_result_annotation`

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Return an owned copy of the normalized tool result annotation.

JSON null is normalized to absence.

#### `parent_uuid`

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Return the parent scope UUID, if the event is nested under a scope.

##### Returns

`Some` parent UUID when the event has a parent scope, otherwise `None`.

#### `propagation_root_uuid`

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Return the stable causal root captured when this event was emitted.

#### `propagation_parent_uuid`

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Return the synthetic parent imported with the propagation context.

#### `propagation_traceparent`

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Return W3C traceparent captured when this event was emitted.

#### `propagation_tracestate`

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Return W3C tracestate captured when this event was emitted.

#### `uuid`

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Return the unique event or span UUID.

##### Returns

The event UUID.

#### `timestamp`

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Return the event timestamp.

##### Returns

The UTC event timestamp.

#### `name`

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Return the human-readable event name.

##### Returns

The event name.

#### `data`

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Return the optional application payload attached to the event.

##### Returns

`Some` payload when event data is present, otherwise `None`.

#### `sanitize_fields`

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Snapshot the observability fields that sanitizers may rewrite.

#### `data_schema`

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Return the optional data schema.

##### Returns

`Some` schema when the event payload declares one, otherwise `None`.

#### `metadata`

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Return the optional metadata attached to the event.

##### Returns

`Some` metadata when present, otherwise `None`.

#### `attributes`

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Return attributes for scope events.

##### Returns

`Some` attributes for scope events, otherwise `None`.

#### `scope_type`

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Return the semantic scope category for scope events.

##### Returns

`Some` legacy \[`ScopeType`] when the event has a category.

#### `input`

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Return the semantic input payload for start events.

##### Returns

`Some` payload for scope-start events with data, otherwise `None`.

#### `output`

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Return the semantic output payload for end events.

##### Returns

`Some` payload for scope-end events with data, otherwise `None`.

#### `model_name`

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Return the normalized model name for LLM events.

##### Returns

`Some` model name when the event profile includes one.

#### `tool_call_id`

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Return the provider-specific tool-call correlation identifier.

##### Returns

`Some` tool call identifier when the event profile includes one.

#### `annotated_request`

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Return the runtime-only annotated LLM request.

##### Returns

`Some` annotated request when the event profile includes one.

#### `annotated_response`

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Return the runtime-only annotated LLM response.

##### Returns

`Some` annotated response when the event profile includes one.

#### `time_to_first_chunk`

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Return the managed stream time to first received chunk, in seconds.

##### Returns

The measured duration on streaming LLM end events, when at least one chunk reached the managed stream wrapper.

#### `is_scope_start`

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Return true for scope-start events.

##### Returns

`true` when the event is a scope-start event.

#### `is_scope_end`

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Return true for scope-end events.

##### Returns

`true` when the event is a scope-end event.

## Trait Implementations

### `impl<'a> Clone for EventView<'a>`

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#### `clone`

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#### `clone_from`

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### `impl Deref for EventView<'_>`

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#### `Target`

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#### `deref`

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### `impl<'a> Copy for EventView<'a>`

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