# Semantic Conventions for Tracing Compatibility Components **Status**: [Experimental][DocumentStatus] This document defines trace semantic conventions used by the compatibility components, e.g. OpenTracing Shim layer. - [OpenTracing](#opentracing) ## OpenTracing `Link`s created by the OpenTracing Shim MUST set `opentracing.ref_type` with one of the accepted values, describing the direct causal relationships between a child Span and a parent Span, as defined by [OpenTracing](https://github.com/opentracing/specification/blob/master/specification.md). | Attribute | Type | Description | Examples | [Requirement Level](https://opentelemetry.io/docs/specs/semconv/general/attribute-requirement-level/) | Stability | |---|---|---|---|---|---| | [`opentracing.ref_type`](../attributes-registry/opentracing.md) | string | Parent-child Reference type [1] | `child_of` | `Recommended` |  | **[1]:** The causal relationship between a child Span and a parent Span. `opentracing.ref_type` has the following list of well-known values. If one of them applies, then the respective value MUST be used; otherwise, a custom value MAY be used. | Value | Description | Stability | |---|---|---| | `child_of` | The parent Span depends on the child Span in some capacity |  | | `follows_from` | The parent Span doesn't depend in any way on the result of the child Span |  | [DocumentStatus]: https://github.com/open-telemetry/opentelemetry-specification/tree/v1.31.0/specification/document-status.md