rust.yaml

# Implementation status for Rust
#
# Legend:
#   '+'     Implemented
#   '-'     Not implemented
#   '?'     Unknown
#   'N/A'   Not applicable to this language
#
sections:
  - name: Traces
    features:
      - heading: '[TracerProvider](specification/trace/api.md#tracerprovider-operations)'
        features:
          - name: Create TracerProvider
            status: '+'
          - name: Get a Tracer
            status: '+'
          - name: Get a Tracer with schema_url
            status: '+'
          - name: Get a Tracer with scope attributes
            status: '+'
          - name: Associate Tracer with InstrumentationScope
            status: '+'
          - name: Safe for concurrent calls
            status: '+'
          - name: Shutdown (SDK only required)
            status: '+'
          - name: ForceFlush (SDK only required)
            status: '+'
      - heading: '[Trace / Context interaction](specification/trace/api.md#context-interaction)'
        features:
          - name: Get active Span
            status: '+'
          - name: Set active Span
            status: '+'
      - heading: '[Tracer](specification/trace/api.md#tracer-operations)'
        features:
          - name: Create a new Span
            status: '+'
          - name: Documentation defines adding attributes at span creation as preferred
            status: '?'
          - name: Get active Span
            status: '+'
          - name: Mark Span active
            status: '+'
          - name: Safe for concurrent calls
            status: '+'
      - heading: '[SpanContext](specification/trace/api.md#spancontext)'
        features:
          - name: IsValid
            status: '+'
          - name: IsRemote
            status: '+'
          - name: Conforms to the W3C TraceContext spec
            status: '+'
          - name: '[Support W3C Trace Context Level 2 randomness](specification/trace/sdk.md#traceid-randomness)'
            status: '?'
      - heading: '[Span](specification/trace/api.md#span)'
        features:
          - name: Create root span
            status: '+'
          - name: Create with default parent (active span)
            status: '+'
          - name: Create with parent from Context
            status: '+'
          - name: No explicit parent Span/SpanContext allowed
            status: '+'
          - name: SpanProcessor.OnStart receives parent Context
            status: '+'
          - name: UpdateName
            status: '+'
          - name: User-defined start timestamp
            status: '+'
          - name: End
            status: '+'
          - name: End with timestamp
            status: '+'
          - name: IsRecording
            status: '+'
          - name: IsRecording becomes false after End
            status: '+'
          - name: Set status with StatusCode (Unset, Ok, Error)
            status: '+'
          - name: Safe for concurrent calls
            status: '+'
          - name: events collection size limit
            status: '+'
          - name: attribute collection size limit
            status: '+'
          - name: links collection size limit
            status: '+'
          - name: '[SpanProcessor.OnEnding](specification/trace/sdk.md#onending)'
            status: '-'
      - heading: '[Span attributes](specification/trace/api.md#set-attributes)'
        features:
          - name: SetAttribute
            status: '+'
          - name: Set order preserved
            status: '+'
          - name: String type
            status: '+'
          - name: Boolean type
            status: '+'
          - name: Double floating-point type
            status: '+'
          - name: Signed int64 type
            status: '+'
          - name: Array of primitives (homogeneous)
            status: '+'
          - name: '`null` values documented as invalid/undefined'
            status: '?'
          - name: Unicode support for keys and string values
            status: '+'
      - heading: '[Span linking](specification/trace/api.md#specifying-links)'
        features:
          - name: Links can be recorded on span creation
            status: '+'
          - name: Links can be recorded after span creation
            status: '+'
          - name: Links order is preserved
            status: '+'
      - heading: '[Span events](specification/trace/api.md#add-events)'
        features:
          - name: AddEvent
            status: '+'
          - name: Add order preserved
            status: '+'
          - name: Safe for concurrent calls
            status: '+'
      - heading: '[Span exceptions](specification/trace/api.md#record-exception)'
        features:
          - name: RecordException
            status: '-'
          - name: RecordException with extra parameters
            status: '-'
      - heading: '[Sampling](specification/trace/sdk.md#sampling)'
        features:
          - name: Allow samplers to modify tracestate
            status: '+'
          - name: ShouldSample gets full parent Context
            status: '+'
          - name: 'Sampler: JaegerRemoteSampler'
            status: '+'
          - name: '[New Span ID created also for non-recording Spans](specification/trace/sdk.md#sdk-span-creation)'
            status: '+'
          - name: '[IdGenerators](specification/trace/sdk.md#id-generators)'
            status: '+'
          - name: '[SpanLimits](specification/trace/sdk.md#span-limits)'
            status: '+'
          - name: '[Built-in `SpanProcessor`s implement `ForceFlush` spec](specification/trace/sdk.md#forceflush-1)'
            status: '+'
          - name: '[Attribute Limits](specification/common/README.md#attribute-limits)'
            status: '?'
          - name: Fetch InstrumentationScope from ReadableSpan
            status: '?'
          - name: '[TraceIdRatioBased sampler implements OpenTelemetry tracestate `th` field](specification/trace/sdk.md#traceidratiobased)'
            status: '?'
          - name: '[CompositeSampler and built-in ComposableSamplers](specification/trace/sdk.md#compositesampler)'
            status: '?'
          - name: '[Sampler: AlwaysRecord](specification/trace/sdk.md#alwaysrecord)'
            status: '?'
  - name: Baggage
    features:
      - name: Basic support
        status: '+'
      - name: Use official header name `baggage`
        status: '+'
  - name: Metrics
    features:
      - name: The API provides a way to set and get a global default `MeterProvider`.
        status: '+'
      - name: It is possible to create any number of `MeterProvider`s.
        status: '+'
      - name: '`MeterProvider` provides a way to get a `Meter`.'
        status: '+'
      - name: '`get_meter` accepts name, `version` and `schema_url`.'
        status: '+'
      - name: '`get_meter` accepts `attributes`.'
        status: '+'
      - name: When an invalid `name` is specified a working `Meter` implementation is returned as a fallback.
        status: '+'
      - name: The fallback `Meter` `name` property keeps its original invalid value.
        status: '+'
      - name: Associate `Meter` with `InstrumentationScope`.
        status: '+'
      - name: '`Counter` instrument is supported.'
        status: '+'
      - name: '`AsynchronousCounter` instrument is supported.'
        status: '+'
      - name: '`Histogram` instrument is supported.'
        status: '+'
      - name: '`AsynchronousGauge` instrument is supported.'
        status: '+'
      - name: '`Gauge` instrument is supported.'
        status: '+'
      - name: '`UpDownCounter` instrument is supported.'
        status: '+'
      - name: '`AsynchronousUpDownCounter` instrument is supported.'
        status: '+'
      - name: Instruments have `name`
        status: '+'
      - name: Instruments have kind.
        status: '+'
      - name: Instruments have an optional unit of measure.
        status: '+'
      - name: Instruments have an optional description.
        status: '+'
      - name:
          A valid instrument MUST be created and warning SHOULD be emitted when multiple instruments are registered under
          the same `Meter` using the same `name`.
        status: '?'
      - name: Duplicate instrument registration name conflicts are resolved by using the first-seen for the stream name.
        status: '?'
      - name: It is possible to register two instruments with same `name` under different `Meter`s.
        status: '+'
      - name: Instrument names conform to the specified syntax.
        status: '?'
      - name: Instrument units conform to the specified syntax.
        status: '+'
      - name: Instrument descriptions conform to the specified syntax.
        status: '?'
      - name: Instrument supports the advisory ExplicitBucketBoundaries parameter.
        status: '?'
      - name: Instrument supports the advisory Attributes parameter.
        status: '?'
      - name: All methods of `MeterProvider` are safe to be called concurrently.
        status: '?'
      - name: All methods of `Meter` are safe to be called concurrently.
        status: '?'
      - name: All methods of any instrument are safe to be called concurrently.
        status: '?'
      - name: '`MeterProvider` allows a `Resource` to be specified.'
        status: '+'
      - name: A specified `Resource` can be associated with all the produced metrics from any `Meter` from the `MeterProvider`.
        status: '+'
      - name:
          The supplied `name`, `version` and `schema_url` arguments passed to the `MeterProvider` are used to create an `InstrumentationLibrary`
          instance stored in the `Meter`.
        status: '+'
      - name:
          The supplied `name`, `version` and `schema_url` arguments passed to the `MeterProvider` are used to create an `InstrumentationScope`
          instance stored in the `Meter`.
        status: '+'
      - name: Configuration is managed solely by the `MeterProvider`.
        status: '+'
      - name: The `MeterProvider` provides methods to update the configuration
        status: '?'
      - name: The updated configuration applies to all already returned `Meter`s.
        status: '?'
      - name: There is a way to register `View`s with a `MeterProvider`.
        status: '+'
      - name: The `View` instrument selection criteria is as specified.
        status: '+'
      - name: The `View` instrument selection criteria supports wildcards.
        status: '+'
      - name: The `View` instrument selection criteria supports the match-all wildcard.
        status: '+'
      - name: The name of the `View` can be specified.
        status: '?'
      - name: The `View` allows configuring the name, description, attributes keys and aggregation of the resulting metric stream.
        status: '+'
      - name: The `View` allows configuring excluded attribute keys of resulting metric stream.
        status: '?'
      - name: The `View` allows configuring the exemplar reservoir of resulting metric stream.
        status: '?'
      - name: The SDK allows more than one `View` to be specified per instrument.
        status: '+'
      - name: The `Drop` aggregation is available.
        status: '+'
      - name: The `Default` aggregation is available.
        status: '+'
      - name: The `Default` aggregation uses the specified aggregation by instrument.
        status: '+'
      - name: The `Sum` aggregation is available.
        status: '+'
      - name: The `LastValue` aggregation is available.
        status: '+'
      - name: The `ExplicitBucketHistogram` aggregation is available.
        status: '+'
      - name: The `ExponentialBucketHistogram` aggregation is available.
        status: '?'
      - name: The metrics Reader implementation supports registering metric Exporters
        status: '+'
      - name: The metrics Reader implementation supports configuring the default aggregation on the basis of instrument kind.
        status: '?'
      - name: The metrics Reader implementation supports configuring the default temporality on the basis of instrument kind.
        status: '+'
      - name: The metrics Exporter has access to the aggregated metrics data (aggregated points, not raw measurements).
        status: '+'
      - name: The metrics Exporter `export` function can not be called concurrently from the same Exporter instance.
        status: '?'
      - name: The metrics Exporter `export` function does not block indefinitely.
        status: '?'
      - name: The metrics Exporter `export` function receives a batch of metrics.
        status: '+'
      - name: The metrics Exporter `export` function returns `Success` or `Failure`.
        status: '+'
      - name: The metrics Exporter provides a `ForceFlush` function.
        status: '+'
      - name: The metrics Exporter `ForceFlush` can inform the caller whether it succeeded, failed or timed out.
        status: '?'
      - name: The metrics Exporter provides a `shutdown` function.
        status: '+'
      - name: The metrics Exporter `shutdown` function do not block indefinitely.
        status: '?'
      - name: The metrics SDK samples `Exemplar`s from measurements.
        status: '?'
      - name: Exemplar sampling can be disabled.
        status: '?'
      - name: The metrics SDK supports SDK-wide exemplar filter configuration
        status: '?'
      - name: The metrics SDK supports `TraceBased` exemplar filter
        status: '?'
      - name: The metrics SDK supports `AlwaysOn` exemplar filter
        status: '?'
      - name: The metrics SDK supports `AlwaysOff` exemplar filter
        status: '?'
      - name: Exemplars retain any attributes available in the measurement that are not preserved by aggregation or view configuration.
        status: '?'
      - name:
          Exemplars contain the associated trace id and span id of the active span in the Context when the measurement was
          taken.
        status: '?'
      - name: Exemplars contain the timestamp when the measurement was taken.
        status: '?'
      - name: The metrics SDK provides an `ExemplarReservoir` interface or extension point.
        status: '?'
      - name: An `ExemplarReservoir` has an `offer` method with access to the measurement value, attributes, `Context` and timestamp.
        status: '?'
      - name:
          The metrics SDK provides a `SimpleFixedSizeExemplarReservoir` that is used by default for all aggregations except
          `ExplicitBucketHistogram`.
        status: '?'
      - name:
          The metrics SDK provides an `AlignedHistogramBucketExemplarReservoir` that is used by default for `ExplicitBucketHistogram`
          aggregation.
        status: '?'
      - name: A metric Producer accepts an optional metric Filter
        status: '?'
      - name: The metric Reader implementation supports registering metric Filter and passing them  its registered metric Producers
        status: '?'
      - name: The metric SDK's metric Producer implementations uses the metric Filter
        status: '?'
      - name: Metric SDK implements [cardinality limit](./specification/metrics/sdk.md#cardinality-limits)
        status: '-'
      - name: Metric SDK supports configuring cardinality limit at MeterReader level
        status: '-'
      - name: Metric SDK supports configuring cardinality limit per metric (using Views)
        status: '-'
      - name: Metric SDK supports per-timeseries cumulative start timestamps
        status: '?'
      - name: The metric SDK's periodic Reader implementation supports the `maxExportBatchSize` parameter
        status: '-'
  - name: Logs
    features:
      - name: LoggerProvider.Get Logger
        status: '+'
      - name: LoggerProvider.Get Logger accepts attributes
        status: '+'
      - name: LoggerProvider.Shutdown
        status: '+'
      - name: LoggerProvider.ForceFlush
        status: '+'
      - name: Logger.Emit(LogRecord)
        status: '+'
      - name: Logger.Emit(LogRecord) with Exception parameter
        status: '?'
      - name: LogRecord.Set EventName
        status: '+'
      - name: Logger.Enabled
        status: '+'
      - name: SimpleLogRecordProcessor
        status: '+'
      - name: BatchLogRecordProcessor
        status: '+'
      - name: Can plug custom LogRecordProcessor
        status: '+'
      - name: LogRecordProcessor.Enabled
        status: '+'
      - name: OTLP/gRPC exporter
        status: '+'
      - name: OTLP/HTTP exporter
        status: '+'
      - name: OTLP File exporter
        status: '-'
      - name: Can plug custom LogRecordExporter
        status: '+'
      - name: Trace Context Injection
        status: '+'
  - name: Resource
    features:
      - name: Create from Attributes
        status: '+'
      - name: Create empty
        status: '+'
      - name: '[Merge (v2)](specification/resource/sdk.md#merge)'
        status: '+'
      - name: Retrieve attributes
        status: '+'
      - name:
          '[Default value](https://github.com/open-telemetry/semantic-conventions/blob/main/docs/resource/README.md#semantic-attributes-with-dedicated-environment-variable)
          for service.name'
        status: '?'
      - name: '[Resource detector](specification/resource/sdk.md#detecting-resource-information-from-the-environment) interface/mechanism'
        status: '+'
      - name: '[Resource detectors populate Schema URL](specification/resource/sdk.md#detecting-resource-information-from-the-environment)'
        status: '+'
  - name: Context Propagation
    features:
      - name: Create Context Key
        status: '+'
      - name: Get value from Context
        status: '+'
      - name: Set value for Context
        status: '+'
      - name: Attach Context
        status: '+'
      - name: Detach Context
        status: '+'
      - name: Get current Context
        status: '+'
      - name: Composite Propagator
        status: '+'
      - name: Global Propagator
        status: '+'
      - name: TraceContext Propagator
        status: '+'
      - name: B3 Propagator
        status: '+'
      - name: Jaeger Propagator
        status: '+'
      - name: OT Propagator
        status: '?'
      - name: OpenCensus Binary Propagator
        status: '?'
      - name: '[TextMapPropagator](specification/context/api-propagators.md#textmap-propagator)'
        status: '?'
      - name: Fields
        status: '+'
      - name: Setter argument
        status: 'N/A'
      - name: Getter argument
        status: 'N/A'
      - name: Getter argument returning Keys
        status: 'N/A'
  - name: Environment Variables
    features:
      - name: OTEL_SDK_DISABLED
        status: '-'
      - name: OTEL_RESOURCE_ATTRIBUTES
        status: '+'
      - name: OTEL_SERVICE_NAME
        status: '+'
      - name: OTEL_LOG_LEVEL
        status: '?'
      - name: OTEL_PROPAGATORS
        status: '-'
      - name: OTEL_BSP_*
        status: '+'
      - name: OTEL_BLRP_*
        status: '+'
      - name: OTEL_EXPORTER_OTLP_*
        status: '+'
      - name: OTEL_EXPORTER_ZIPKIN_*
        status: '-'
      - name: OTEL_TRACES_EXPORTER
        status: '-'
      - name: OTEL_METRICS_EXPORTER
        status: '-'
      - name: OTEL_LOGS_EXPORTER
        status: '-'
      - name: OTEL_SPAN_ATTRIBUTE_COUNT_LIMIT
        status: '+'
      - name: OTEL_SPAN_ATTRIBUTE_VALUE_LENGTH_LIMIT
        status: '?'
      - name: OTEL_SPAN_EVENT_COUNT_LIMIT
        status: '+'
      - name: OTEL_SPAN_LINK_COUNT_LIMIT
        status: '+'
      - name: OTEL_EVENT_ATTRIBUTE_COUNT_LIMIT
        status: '?'
      - name: OTEL_LINK_ATTRIBUTE_COUNT_LIMIT
        status: '?'
      - name: OTEL_LOGRECORD_ATTRIBUTE_COUNT_LIMIT
        status: '-'
      - name: OTEL_LOGRECORD_ATTRIBUTE_VALUE_LENGTH_LIMIT
        status: '-'
      - name: OTEL_TRACES_SAMPLER
        status: '+'
      - name: OTEL_TRACES_SAMPLER_ARG
        status: '+'
      - name: OTEL_ATTRIBUTE_VALUE_LENGTH_LIMIT
        status: '?'
      - name: OTEL_ATTRIBUTE_COUNT_LIMIT
        status: '?'
      - name: OTEL_METRIC_EXPORT_INTERVAL
        status: '?'
      - name: OTEL_METRIC_EXPORT_TIMEOUT
        status: '?'
      - name: OTEL_METRICS_EXEMPLAR_FILTER
        status: '?'
      - name: OTEL_EXPORTER_OTLP_METRICS_TEMPORALITY_PREFERENCE
        status: '?'
      - name: OTEL_EXPORTER_OTLP_METRICS_DEFAULT_HISTOGRAM_AGGREGATION
        status: '?'
      - name: OTEL_CONFIG_FILE
        status: '?'
  - name: Declarative configuration
    features:
      - name: '`Parse` a configuration file'
        status: '?'
      - name: The `Parse` operation accepts the configuration YAML file format
        status: '?'
      - name: The `Parse` operation performs environment variable substitution
        status: '?'
      - name: The `Parse` operation returns configuration model
        status: '?'
      - name: The `Parse` operation resolves plugin component configuration to `properties`
        status: '?'
      - name: '`Create` SDK components'
        status: '?'
      - name: The `Create` operation accepts configuration model
        status: '?'
      - name: The `Create` operation returns `TracerProvider`
        status: '?'
      - name: The `Create` operation returns `MeterProvider`
        status: '?'
      - name: The `Create` operation returns `LoggerProvider`
        status: '?'
      - name: The `Create` operation returns `Propagators`
        status: '?'
      - name: The `Create` operation calls `CreateComponent` of corresponding `PluginComponentProvider` when encountering plugin components
        status: '?'
      - name: Register a `PluginComponentProvider`
        status: '?'
  - name: Exporters
    features:
      - name: '[Exporter interface](specification/trace/sdk.md#span-exporter)'
        status: '+'
      - name: '[Exporter interface has `ForceFlush`](specification/trace/sdk.md#forceflush-2)'
        status: '-'
      - name: Standard output (logging)
        status: '+'
      - name: In-memory (mock exporter)
        status: '+'
      - heading: '**[OTLP](specification/protocol/otlp.md)**'
        features:
          - name: OTLP/gRPC Exporter
            status: '+'
          - name: OTLP/HTTP binary Protobuf Exporter
            status: '+'
          - name: OTLP/HTTP JSON Protobuf Exporter
            status: '?'
          - name: OTLP/HTTP gzip Content-Encoding support
            status: '?'
          - name: Concurrent sending
            status: '+'
          - name: Honors retryable responses with backoff
            status: '?'
          - name: Honors non-retryable responses
            status: '?'
          - name: Honors throttling response
            status: '?'
          - name: Multi-destination spec compliance
            status: '?'
          - name: SchemaURL in ResourceSpans and ScopeSpans
            status: '?'
          - name: SchemaURL in ResourceMetrics and ScopeMetrics
            status: '?'
          - name: SchemaURL in ResourceLogs and ScopeLogs
            status: '?'
          - name: Honors the [user agent spec](specification/protocol/exporter.md#user-agent)
            status: '?'
          - name:
              '[Partial Success](https://github.com/open-telemetry/opentelemetry-proto/blob/main/docs/specification.md#partial-success)
              messages are handled and logged for OTLP/gRPC'
            status: '?'
          - name:
              '[Partial Success](https://github.com/open-telemetry/opentelemetry-proto/blob/main/docs/specification.md#partial-success-1)
              messages are handled and logged for OTLP/HTTP'
            status: '?'
          - name: Metric Exporter configurable temporality preference
            status: '?'
          - name: Metric Exporter configurable default aggregation
            status: '?'
      - heading: '**[Zipkin](specification/trace/sdk_exporters/zipkin.md)**'
        features:
          - name: Zipkin V1 JSON
            status: '-'
          - name: Zipkin V1 Thrift
            status: '-'
          - name: Zipkin V2 JSON
            status: '+'
          - name: Zipkin V2 Protobuf
            status: '-'
          - name: Service name mapping
            status: '+'
          - name: SpanKind mapping
            status: '+'
          - name: InstrumentationLibrary mapping
            status: '+'
          - name: InstrumentationScope mapping
            status: '?'
          - name: Boolean attributes
            status: '+'
          - name: Array attributes
            status: '+'
          - name: Status mapping
            status: '+'
          - name: Error Status mapping
            status: '+'
          - name: Event attributes mapping to Annotations
            status: '+'
          - name: Integer microseconds in timestamps
            status: '+'
      - heading: '**Prometheus**'
        features:
          - name: '[Metadata Deduplication](specification/compatibility/prometheus_and_openmetrics.md#metric-metadata-1)'
            status: '+'
          - name: '[Name Sanitization](specification/compatibility/prometheus_and_openmetrics.md#metric-metadata-1)'
            status: '+'
          - name: '[UNIT Metadata](specification/compatibility/prometheus_and_openmetrics.md#metric-metadata-1)'
            status: '-'
          - name: '[Unit Suffixes](specification/compatibility/prometheus_and_openmetrics.md#metric-metadata-1)'
            status: '+'
          - name: '[Unit Full Words](specification/compatibility/prometheus_and_openmetrics.md#metric-metadata-1)'
            status: '+'
          - name: '[HELP Metadata](specification/compatibility/prometheus_and_openmetrics.md#metric-metadata-1)'
            status: '+'
          - name: '[TYPE Metadata](specification/compatibility/prometheus_and_openmetrics.md#metric-metadata-1)'
            status: '+'
          - name: '[otel_scope_name and otel_scope_version labels on all Metrics](specification/compatibility/prometheus_and_openmetrics.md#instrumentation-scope-1)'
            status: '+'
          - name: '[otel_scope_[attribute] labels on all Metrics](specification/compatibility/prometheus_and_openmetrics.md#instrumentation-scope-1)'
            status: '-'
          - name: '[otel_scope labels can be disabled](specification/compatibility/prometheus_and_openmetrics.md#instrumentation-scope-1)'
            status: '+'
          - name: '[Gauges become Prometheus Gauges](specification/compatibility/prometheus_and_openmetrics.md#gauges-1)'
            status: '+'
          - name: '[Cumulative Monotonic Sums become Prometheus Counters](specification/compatibility/prometheus_and_openmetrics.md#sums)'
            status: '+'
          - name: '[Prometheus Counters have _total suffix by default](specification/compatibility/prometheus_and_openmetrics.md#sums)'
            status: '+'
          - name: '[Prometheus Counters _total suffixing can be disabled](specification/compatibility/prometheus_and_openmetrics.md#sums)'
            status: '-'
          - name: '[Cumulative Non-Monotonic Sums become Prometheus Gauges](specification/compatibility/prometheus_and_openmetrics.md#sums)'
            status: '+'
          - name: '[Delta Non-Monotonic Sums become Cumulative Prometheus Counters](specification/compatibility/prometheus_and_openmetrics.md#sums)'
            status: '-'
          - name: '[Cumulative Histograms become Prometheus Histograms](specification/compatibility/prometheus_and_openmetrics.md#histograms-1)'
            status: '+'
          - name: '[Delta Histograms become Cumulative Prometheus Histograms](specification/compatibility/prometheus_and_openmetrics.md#histograms-1)'
            status: '-'
          - name: '[Attributes Keys are Sanitized](specification/compatibility/prometheus_and_openmetrics.md#metric-attributes)'
            status: '+'
          - name: '[Colliding sanitized attribute keys are merged](specification/compatibility/prometheus_and_openmetrics.md#metric-attributes)'
            status: '+'
          - name: '[Exemplars for Histograms and Monotonic sums](specification/compatibility/prometheus_and_openmetrics.md#exemplars-1)'
            status: '-'
          - name: '[`target_info` metric from Resource](specification/compatibility/prometheus_and_openmetrics.md#resource-attributes-1)'
            status: '+'
  - name: OpenCensus Compatibility
    features:
      - name: '[Trace Bridge](specification/compatibility/opencensus.md#trace-bridge)'
        status: '?'
      - name: '[Metric Bridge](specification/compatibility/opencensus.md#metrics--stats)'
        status: '?'
  - name: OpenTracing Compatibility
    features:
      - name: '[Create OpenTracing Shim](specification/compatibility/opentracing.md#create-an-opentracing-tracer-shim)'
        status: '?'
      - name: '[Tracer](specification/compatibility/opentracing.md#tracer-shim)'
        status: '?'
      - name: '[Span](specification/compatibility/opentracing.md#span-shim)'
        status: '?'
      - name: '[SpanContext](specification/compatibility/opentracing.md#spancontext-shim)'
        status: '?'
      - name: '[ScopeManager](specification/compatibility/opentracing.md#scopemanager-shim)'
        status: '?'
      - name: Error mapping for attributes/events
        status: '?'
      - name: Migration to OpenTelemetry guide
        status: '?'