Maple Telemetry Conventions

Reference for the language-agnostic OpenTelemetry conventions Maple uses across TypeScript (apps/api, Cloudflare workers in packages/effect-sdk/), Rust (apps/ingest), and future Python services. These conventions are load-bearing — Tinybird materialized views pre-extract certain attribute keys into columns, dashboards filter on Title Case status strings, and sampling-aware throughput math relies on the SampleRate column. Use the exact attribute spellings here in every language.

When to apply

• Adding setAttribute / Effect.annotateCurrentSpan / Span::current().record(...) / #[instrument(fields(...))] to any code path
• Setting span status (Ok / Error / Unset)
• Wiring a new query through WarehouseQueryService.compiledQuery() (the context and profile options become span attributes)
• Configuring an OTLP exporter, tracer provider, or resource builder
• Introducing a new pre-extracted MV column or a new vendor attribute under maple.*
• Reviewing a PR that touches apps/api/src/services/WarehouseQueryService.ts, apps/ingest/src/main.rs, apps/api/src/app.ts, packages/effect-sdk/src/cloudflare/, or packages/domain/src/tinybird/materializations.ts

Index