> ## Documentation Index > Fetch the complete documentation index at: https://docs.chronosphere.io/llms.txt > Use this file to discover all available pages before exploring further. # ReadTraceTailSamplingRules ## OpenAPI ````yaml openapi/api_v1_config_openapi3_DOCUMENTATION_ONLY.json GET /api/v1/config/trace-tail-sampling-rules openapi: 3.0.3 info: description: > The Config API provides standard HTTP/JSON REST endpoints for creating, reading, updating, deleting, and listing configurable Chronosphere resources. Use this link to download the raw Swagger specification: /api/v1/config/swagger.json title: Config V1 API version: v1 servers: - url: https://{tenant}.chronosphere.io variables: tenant: default: tenant description: tenant ID assigned by the service provider security: - ApiKeyAuth: [] tags: - name: ConfigV1 paths: /api/v1/config/trace-tail-sampling-rules: get: tags: - TraceTailSamplingRules operationId: ReadTraceTailSamplingRules responses: '200': content: application/json: schema: $ref: >- #/components/schemas/configv1ReadTraceTailSamplingRulesResponse description: A successful response. '404': content: application/json: schema: $ref: '#/components/schemas/apiError' description: >- Cannot read the TraceTailSamplingRules because TraceTailSamplingRules has not been created. '500': content: application/json: schema: $ref: '#/components/schemas/apiError' description: An unexpected error response. default: content: application/json: schema: $ref: '#/components/schemas/genericError' description: An undefined error response. components: schemas: configv1ReadTraceTailSamplingRulesResponse: properties: trace_tail_sampling_rules: $ref: '#/components/schemas/configv1TraceTailSamplingRules' type: object apiError: properties: message: description: An error message describing what went wrong. type: string type: object genericError: additionalProperties: true type: object configv1TraceTailSamplingRules: description: Root object containing all tail sampling rules (for a tenant). properties: created_at: description: Timestamp of when the rule was created. format: date-time readOnly: true type: string default_sample_rate: allOf: - $ref: '#/components/schemas/configv1DefaultSampleRate' description: >- Optional. By default, all traces not matching the defined rules are kept. You can override this behavior by providing a default sample rate. rules: description: >- Optional. Specifies a list of rules and a sampling rate to apply. Rules are evaluated in order until a match is found. If no sample rate is specified, the default sample rate is applied. items: $ref: '#/components/schemas/configv1TraceTailSamplingRule' type: array updated_at: description: Timestamp of when the rule was updated. format: date-time readOnly: true type: string type: object configv1DefaultSampleRate: properties: enabled: description: Determines whether to override the default sample rate. type: boolean sample_rate: description: >- Specifies the percentage of traces to keep, which must be a number between `0` and `1`, inclusive, where `1` equates to 100 percent. format: double type: number type: object configv1TraceTailSamplingRule: description: Contains configuration for one tail sampling rule. properties: created_at: description: Timestamp of when the rule was created. format: date-time type: string filter: allOf: - $ref: '#/components/schemas/configv1TraceSearchFilter' description: >- Filter criteria applied to each trace to determine whether the trace is a match. name: description: A human-readable name of the rule. type: string sample_rate: description: >- Specifies the percentage of traces to keep, which must be a number between `0` and `1`, inclusive, where `1` equates to 100 percent. format: double type: number system_name: description: >- Name used as the metric label value for metrics that are emitted from this rule. type: string updated_at: description: Timestamp of when the rule was updated. format: date-time type: string type: object configv1TraceSearchFilter: properties: scope_filter: allOf: - $ref: '#/components/schemas/TraceSearchFilterScopeFilter' description: >- Scope filter that defines which spans within matching traces contribute to metrics calculation. span: description: >- Specifies the span conditions to match on. All conditions must be true in a single span for the span to be considered a match. If `span_count` is specified, the number of spans within the trace that match span conditions must be within `[min, max]`. You can specify multiple span conditions, and each can be satisfied by any number of spans within the trace. items: $ref: '#/components/schemas/TraceSearchFilterSpanFilter' type: array trace: allOf: - $ref: '#/components/schemas/TraceSearchFilterTraceFilter' description: Trace-level filter criteria (effectively matching the root span). type: object TraceSearchFilterScopeFilter: properties: span_scopes: description: >- Specifies the span filters that define which spans contribute to the metrics calculation. Only spans matching these filters will be included in the metrics aggregation. items: $ref: '#/components/schemas/TraceSearchFilterSpanFilter' type: array type: object TraceSearchFilterSpanFilter: properties: duration: allOf: - $ref: '#/components/schemas/TraceSearchFilterDurationFilter' description: Matches the duration of the candidate span. error: allOf: - $ref: '#/components/schemas/TraceSearchFilterBoolFilter' description: Matches the error status of the candidate span. is_root_span: allOf: - $ref: '#/components/schemas/TraceSearchFilterBoolFilter' description: >- Matches the root span of a trace. For example, if the parent span has no child spans. match_type: allOf: - $ref: '#/components/schemas/SpanFilterSpanFilterMatchType' description: >- If `INCLUDE`, includes all traces that have at least one (or `span_count`) spans matching the query. If `EXCLUDE`, excludes all traces that have at least one (or `span_count`) spans matching the query. operation: allOf: - $ref: '#/components/schemas/TraceSearchFilterStringFilter' description: Matches the operation of the candidate span. parent_operation: allOf: - $ref: '#/components/schemas/TraceSearchFilterStringFilter' description: >- If not a root span, matches the operation of the candidate span's parent span parent_service: allOf: - $ref: '#/components/schemas/TraceSearchFilterStringFilter' description: >- If not a root span, matches the service of the candidate span's parent span. service: allOf: - $ref: '#/components/schemas/TraceSearchFilterStringFilter' description: Matches the service of the candidate span. span_count: allOf: - $ref: '#/components/schemas/TraceSearchFilterCountFilter' description: >- Defines the number of spans that must match the criteria defined by the span query. Defaults to requiring that at least one span matches the span query. tags: description: Matches the tags of the candidate span. items: $ref: '#/components/schemas/TraceSearchFilterTagFilter' type: array type: object TraceSearchFilterTraceFilter: properties: duration: allOf: - $ref: '#/components/schemas/TraceSearchFilterDurationFilter' description: Matches traces based on the duration of the entire trace. error: allOf: - $ref: '#/components/schemas/TraceSearchFilterBoolFilter' description: Matches traces based on the top-level error status. type: object TraceSearchFilterDurationFilter: properties: max_secs: description: Maximum duration, in seconds, required for a span or trace to match. format: double type: number min_secs: description: Minimum duration, in seconds, required for a span or trace to match. format: double type: number type: object TraceSearchFilterBoolFilter: properties: value: description: The value of the filter compared to the target trace or span field. type: boolean type: object SpanFilterSpanFilterMatchType: enum: - INCLUDE - EXCLUDE type: string TraceSearchFilterStringFilter: properties: in_values: description: >- Values the filter tests against when using `IN` or `NOT_IN` match type. items: type: string type: array match: allOf: - $ref: '#/components/schemas/StringFilterStringFilterMatchType' description: >- Specifies the comparison operator for the query. If `EXACT`, compared strings must have the exact value of the query value. value: description: The value of the filter compared to the target trace or span field. type: string type: object TraceSearchFilterCountFilter: properties: max: description: Maximum number of spans that must match a span query, inclusive. format: int32 type: integer min: description: Minimum number of spans that must match a span query, inclusive. format: int32 type: integer type: object TraceSearchFilterTagFilter: properties: key: description: The key or name of the span tag that this filter inspects. type: string numeric_value: allOf: - $ref: '#/components/schemas/TraceSearchFilterNumericFilter' description: >- If the query matches the tag with the specified key, and the value type is `numeric`, specifies the matcher used to evaluate the span tag value. value: allOf: - $ref: '#/components/schemas/TraceSearchFilterStringFilter' description: >- If the query matches the tag with the specified key, and the value type is a `string`, specifies the matcher used to evaluate the span tag value. type: object StringFilterStringFilterMatchType: enum: - EXACT - REGEX - EXACT_NEGATION - REGEX_NEGATION - IN - NOT_IN type: string TraceSearchFilterNumericFilter: properties: comparison: allOf: - $ref: '#/components/schemas/NumericFilterComparisonType' description: >- The comparison operation to apply to an input against the given query value. value: description: The filter value used in comparison against match candidates. format: double type: number type: object NumericFilterComparisonType: enum: - EQUAL - NOT_EQUAL - GREATER_THAN - GREATER_THAN_OR_EQUAL - LESS_THAN - LESS_THAN_OR_EQUAL type: string securitySchemes: ApiKeyAuth: description: Chronosphere API token in: header name: API-Token type: apiKey ````