Review Telemetry

Review Telemetry

Follow shared context and the findings contract. Own emitted names, dimensions, units, cardinality, redaction and duplicate instrumentation, on which dashboards, alerts and queries depend.

Route symbol names to review-naming, cost-only findings to review-perf, and stale/contradictory docs to review-consistency. Keep emitted-contract defects here, combining signal and measured-cost evidence rather than duplicating them.

Procedure

1. Inventory changed signals from instrument definitions and telemetry tests or exported-signal snapshots, not surrounding prose. Locate comparable signals and consumers.
2. Apply the contract and emission questions below.
3. Return exact emitted evidence and impact; apply review-perf measurement requirements to per-emission cost claims.

Signal-contract questions

• Follow OpenTelemetry semantic names/values for metrics, spans and attributes. Reuse sibling dot-separated namespaces (oxidizer.hyper), name shapes, units and attribute sets rather than inventing parallel vocabulary.
• Treat additions/removals/renames in stable metric dimensions as breaking changes to dependent queries/dashboards. Emit a sentinel for missing values, never drop the dimension.
• Keep service-specific dimensions out of shared defaults; expose an extension for the consumer to emit.
• Require metrics/logging layer names at construction, with sensible standard pipeline defaults, and expose names on pipeline context.
• Put convention-carried units in instruments, not metric names.

Emission questions

• Bound metric attributes and span names: no request IDs, raw URIs, user or tenant identifiers. Use enumerable error kinds or route templates, e.g. connect.hyper.timeout or request.connect.connection_refused. Convention-appropriate span/log attributes may be high-cardinality (url.full on HTTP client spans); assess sensitivity/backend cost, not cardinality alone. Order composite labels low-to-high cardinality so prefixes remain queryable.
• Avoid per-emission String allocation: prefer &'static str, Cow<'static, str> or cached attributes. Cache instruments too.
• Does middleware/client instrumentation already emit retry, timeout, breaker or request signals? Remove duplicate call-site metrics/logs and reuse it.
• Require a named consumer for new spans. If no backend consumes them, prefer regular tracing APIs, metrics or logs. Per-request measurements are metrics; logs describe events an operator must read.
• Reuse an existing tracing log front end rather than boxing/storing a local logger provider.
• Route all user/customer data through repository classification/redaction before emission.

Proof and coverage

Name the exact signal/attributes and violated convention or sibling, with decisive emitted evidence, operator impact and corrected instrumentation. Telemetry tables/dashboards can prove consumer dependence for a breaking rename, not the emitted definition.

If comparable components instrument behavior but this change adds none, note that once; do not demand unnecessary instrumentation.

Coverage: signals reviewed and names/attribute sets unconfirmed by definitions or telemetry tests.