> For clean Markdown of any page, append .md to the page URL. > For a complete documentation index, see https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/llms.txt. > For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://docs.nvidia.com/nemo/relay/_mcp/server. # Module event > Lifecycle event types and builder-backed event constructors. Event types for Agent Trajectory Observability Format (ATOF) runtime events. Generated from `cargo doc --no-deps -p nemo-relay -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`. Lifecycle event types and builder-backed event constructors. Event types for Agent Trajectory Observability Format (ATOF) runtime events. ## Structs * [BaseEvent](/reference/api/rust-library-reference/nemo-relay/api/event/struct-baseevent): Shared event metadata carried by every ATOF event. * [CategoryProfile](/reference/api/rust-library-reference/nemo-relay/api/event/struct-categoryprofile): Category-specific profile data. * [DataSchema](/reference/api/rust-library-reference/nemo-relay/api/event/struct-dataschema): Identifier for the schema that describes an event's opaque `data` payload. * [EventCategory](/reference/api/rust-library-reference/nemo-relay/api/event/struct-eventcategory): Semantic category carried by ATOF `category`. * [EventSanitizeFields](/reference/api/rust-library-reference/nemo-relay/api/event/struct-eventsanitizefields): Observability fields that event sanitizers may rewrite. * [FiniteF64](/reference/api/rust-library-reference/nemo-relay/api/event/struct-finitef64): A finite IEEE 754 double-precision value. * [HistogramBoundaries](/reference/api/rust-library-reference/nemo-relay/api/event/struct-histogramboundaries): Explicit histogram bucket boundaries that are finite and strictly increasing. * [InstrumentDescriptor](/reference/api/rust-library-reference/nemo-relay/api/event/struct-instrumentdescriptor): Descriptor fields shared by all recordings of an instrument. * [InstrumentName](/reference/api/rust-library-reference/nemo-relay/api/event/struct-instrumentname): An OpenTelemetry instrument name together with its canonical form. * [MarkEvent](/reference/api/rust-library-reference/nemo-relay/api/event/struct-markevent): ATOF point-in-time mark event. * [MetricAttributes](/reference/api/rust-library-reference/nemo-relay/api/event/struct-metricattributes): A deterministic map of typed OpenTelemetry metric attributes. * [MetricEnvelope](/reference/api/rust-library-reference/nemo-relay/api/event/struct-metricenvelope): Payload stored in a mark using [`METRIC_DATA_SCHEMA_NAME`](/reference/api/rust-library-reference/nemo-relay/api/event/constant-metric-data-schema-name). * [MetricMeasurement](/reference/api/rust-library-reference/nemo-relay/api/event/struct-metricmeasurement): One recording operation in a Relay metric mark. * [MetricValidationError](/reference/api/rust-library-reference/nemo-relay/api/event/struct-metricvalidationerror): Validation error for a Relay metric envelope. * [ParseLogSeverityError](/reference/api/rust-library-reference/nemo-relay/api/event/struct-parselogseverityerror): Error returned when parsing an unsupported log severity. * [PendingMarkSpec](/reference/api/rust-library-reference/nemo-relay/api/event/struct-pendingmarkspec): Mark requested by middleware for materialization by a lifecycle owner. * [ScopeEvent](/reference/api/rust-library-reference/nemo-relay/api/event/struct-scopeevent): ATOF scope lifecycle event. * [ValidatedMetricMeasurement](/reference/api/rust-library-reference/nemo-relay/api/event/struct-validatedmetricmeasurement): Parsed metric measurement that is safe for OTLP export. ## Enums * [AttributeValue](/reference/api/rust-library-reference/nemo-relay/api/event/enum-attributevalue): Typed OpenTelemetry attribute values, including homogeneous primitive arrays. * [Event](/reference/api/rust-library-reference/nemo-relay/api/event/enum-event): Tagged union covering the two ATOF event kinds emitted by the runtime. * [LogSeverity](/reference/api/rust-library-reference/nemo-relay/api/event/enum-logseverity): Severity attached to a mark that may be projected as an OpenTelemetry log. * [MetricKind](/reference/api/rust-library-reference/nemo-relay/api/event/enum-metrickind): OpenTelemetry instrument kind represented by a metric measurement mark. * [MetricValue](/reference/api/rust-library-reference/nemo-relay/api/event/enum-metricvalue): One typed metric value accepted by Relay's metric schema. * [MetricValueType](/reference/api/rust-library-reference/nemo-relay/api/event/enum-metricvaluetype): Numeric representation used by a metric measurement. * [ScopeCategory](/reference/api/rust-library-reference/nemo-relay/api/event/enum-scopecategory): Agent Trajectory Observability Format (ATOF) lifecycle phase for a scope event. ## Constants * [ATOF\_VERSION](/reference/api/rust-library-reference/nemo-relay/api/event/constant-atof-version): Agent Trajectory Observability Format (ATOF) protocol version emitted by this runtime. * [LOG\_SEVERITY\_METADATA\_KEY](/reference/api/rust-library-reference/nemo-relay/api/event/constant-log-severity-metadata-key): Reserved metadata key carrying the canonical severity of a mark exported as a log. * [METRIC\_DATA\_SCHEMA\_NAME](/reference/api/rust-library-reference/nemo-relay/api/event/constant-metric-data-schema-name): Relay-owned schema name for mark payloads containing metric measurements. * [METRIC\_DATA\_SCHEMA\_VERSION](/reference/api/rust-library-reference/nemo-relay/api/event/constant-metric-data-schema-version): Current Relay-owned metric measurement schema version. ## Traits * [EventNormalizationExt](/reference/api/rust-library-reference/nemo-relay/api/event/trait-eventnormalizationext): Core-only normalized LLM accessors for ATOF events. ## Functions * [attributes\_from\_handle](/reference/api/rust-library-reference/nemo-relay/api/event/fn-attributes-from-handle): Convert handle bitflags into ATOF attributes. * [llm\_attributes\_to\_strings](/reference/api/rust-library-reference/nemo-relay/api/event/fn-llm-attributes-to-strings): Convert LLM bitflags into ATOF attributes. * [scope\_attributes\_to\_strings](/reference/api/rust-library-reference/nemo-relay/api/event/fn-scope-attributes-to-strings): Convert scope bitflags into ATOF attributes. * [tool\_attributes\_to\_strings](/reference/api/rust-library-reference/nemo-relay/api/event/fn-tool-attributes-to-strings): Convert tool bitflags into ATOF attributes. * [validate\_metric\_measurements](/reference/api/rust-library-reference/nemo-relay/api/event/fn-validate-metric-measurements): Validate a complete list of metric measurements atomically. > Lifecycle event types and builder-backed event constructors. Event types for Agent Trajectory Observability Format (ATOF) runtime events. ## Docs - [Struct Base Event](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/struct-baseevent.md): Shared event metadata carried by every ATOF event. - [Struct Category Profile](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/struct-categoryprofile.md): Category-specific profile data. - [Struct Data Schema](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/struct-dataschema.md): Identifier for the schema that describes an event's opaque `data` payload. - [Struct Event Category](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/struct-eventcategory.md): Semantic category carried by ATOF `category`. - [Struct Event Sanitize Fields](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/struct-eventsanitizefields.md): Observability fields that event sanitizers may rewrite. - [Struct Finite F64](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/struct-finitef64.md): A finite IEEE 754 double-precision value. - [Struct Histogram Boundaries](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/struct-histogramboundaries.md): Explicit histogram bucket boundaries that are finite and strictly increasing. - [Struct Instrument Descriptor](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/struct-instrumentdescriptor.md): Descriptor fields shared by all recordings of an instrument. - [Struct Instrument Name](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/struct-instrumentname.md): An OpenTelemetry instrument name together with its canonical form. - [Struct Mark Event](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/struct-markevent.md): ATOF point-in-time mark event. - [Struct Metric Attributes](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/struct-metricattributes.md): A deterministic map of typed OpenTelemetry metric attributes. - [Struct Metric Envelope](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/struct-metricenvelope.md): Payload stored in a mark using `METRIC_DATA_SCHEMA_NAME`. - [Struct Metric Measurement](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/struct-metricmeasurement.md): One recording operation in a Relay metric mark. - [Struct Metric Validation Error](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/struct-metricvalidationerror.md): Validation error for a Relay metric envelope. - [Struct Parse LogSeverity Error](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/struct-parselogseverityerror.md): Error returned when parsing an unsupported log severity. - [Struct Pending Mark Spec](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/struct-pendingmarkspec.md): Mark requested by middleware for materialization by a lifecycle owner. - [Struct Scope Event](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/struct-scopeevent.md): ATOF scope lifecycle event. - [Struct Validated Metric Measurement](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/struct-validatedmetricmeasurement.md): Parsed metric measurement that is safe for OTLP export. - [Enum Attribute Value](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/enum-attributevalue.md): Typed OpenTelemetry attribute values, including homogeneous primitive arrays. - [Enum Event](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/enum-event.md): Tagged union covering the two ATOF event kinds emitted by the runtime. - [Enum LogSeverity](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/enum-logseverity.md): Severity attached to a mark that may be projected as an OpenTelemetry log. - [Enum Metric Kind](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/enum-metrickind.md): OpenTelemetry instrument kind represented by a metric measurement mark. - [Enum Metric Value](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/enum-metricvalue.md): One typed metric value accepted by Relay's metric schema. - [Enum Metric Value Type](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/enum-metricvaluetype.md): Numeric representation used by a metric measurement. - [Enum Scope Category](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/enum-scopecategory.md): Agent Trajectory Observability Format (ATOF) lifecycle phase for a scope event. - [Constant ATOF_VERSION](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/constant-atof-version.md): Agent Trajectory Observability Format (ATOF) protocol version emitted by this runtime. - [Constant LOG_SEVERITY_METADATA_KEY](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/constant-log-severity-metadata-key.md): Reserved metadata key carrying the canonical severity of a mark exported as a log. - [Constant METRIC_DATA_SCHEMA_NAME](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/constant-metric-data-schema-name.md): Relay-owned schema name for mark payloads containing metric measurements. - [Constant METRIC_DATA_SCHEMA_VERSION](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/constant-metric-data-schema-version.md): Current Relay-owned metric measurement schema version. - [Trait Event Normalization Ext](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/trait-eventnormalizationext.md): Core-only normalized LLM accessors for ATOF events. - [Function attributes_from_handle](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/fn-attributes-from-handle.md): Convert handle bitflags into ATOF attributes. - [Function llm_attributes_to_strings](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/fn-llm-attributes-to-strings.md): Convert LLM bitflags into ATOF attributes. - [Function scope_attributes_to_strings](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/fn-scope-attributes-to-strings.md): Convert scope bitflags into ATOF attributes. - [Function tool_attributes_to_strings](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/fn-tool-attributes-to-strings.md): Convert tool bitflags into ATOF attributes. - [Function validate_metric_measurements](https://docs.nvidia.com/nemo/relay/v0.10.1/reference/api/rust-library-reference/nemo-relay/api/event/fn-validate-metric-measurements.md): Validate a complete list of metric measurements atomically.