## Source

`TODO`: "Automatic tracing spans + UI for it"

## Acceptance

- [x] Decision: instrument **all boundaries** in the first version: HTTP/API, Durable Object/project room, collaboration sync, device protocol/run, MCP tool call and auth.
- [ ] Define the trace model and attributes for those spans.
- [ ] Instrument those boundaries with Effect spans and consistent attributes, propagating context across the Worker and Durable Object.
- [ ] Define sampling, retention and redaction; no project source, credentials or personal data in span attributes.
- [ ] Export traces to a chosen backend and make them available locally in development.
- [ ] Add a UI that opens a trace from the place an error or slow request is shown, with a readable waterfall.
- [ ] Add tests for span creation and context propagation, and document how to add a span.


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