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+# Spec in spans
+
+Specifying the structure of trace and metric data in logs.
+
+## Motivation
+
+Why should we make this change? What new value would it bring? What use cases does it enable?
+
+## Explanation
+
+Explain the proposed change as though it was already implemented and you were explaining it to a user. Depending on which layer the proposal addresses, the "user" may vary, or there may even be multiple.
+
+We encourage you to use examples, diagrams, or whatever else makes the most sense!
+
+## Internal details
+
+From a technical perspective, how do you propose accomplishing the proposal? In particular, please explain:
+
+* How the change would impact and interact with existing functionality
+* Likely error modes (and how to handle them)
+* Corner cases (and how to handle them)
+
+While you do not need to prescribe a particular implementation - indeed, OTEPs should be about **behaviour**, not implementation! - it may be useful to provide at least one suggestion as to how the proposal *could* be implemented. This helps reassure reviewers that implementation is at least possible, and often helps them inspire them to think more deeply about trade-offs, alternatives, etc.
+
+## Trade-offs and mitigations
+
+What are some (known!) drawbacks? What are some ways that they might be mitigated?
+
+Note that mitigations do not need to be complete *solutions*, and that they do not need to be accomplished directly through your proposal. A suggested mitigation may even warrant its own OTEP!
+
+## Prior art and alternatives
+
+What are some prior and/or alternative approaches? For instance, is there a corresponding feature in OpenTracing or OpenCensus? What are some ideas that you have rejected?
+
+## Open questions
+
+What are some questions that you know aren't resolved yet by the OTEP? These may be questions that could be answered through further discussion, implementation experiments, or anything else that the future may bring.
+
+## Future possibilities
+
+What are some future changes that this proposal would enable?