183-java-observability-tracing-opentelemetry

name	183-java-observability-tracing-opentelemetry
description	Use when you need to implement or improve distributed tracing with OpenTelemetry in Java — including trace/span modeling, context propagation, semantic conventions, span attributes/events/status, sampling strategy, baggage usage, privacy safeguards, and backend integration with OTLP collectors. This should trigger for requests such as Improve tracing; Apply OpenTelemetry tracing; Add distributed tracing; Refactor tracing instrumentation; Instrument Java services with OpenTelemetry spans. Part of Plinth Toolkit
license	Apache-2.0
metadata	{"author":"Juan Antonio Breña Moral","version":"0.18.0"}

Java Distributed Tracing with OpenTelemetry

Implement robust distributed tracing in Java with OpenTelemetry by modeling meaningful spans, preserving context propagation, and instrumenting critical business and infrastructure paths with low-overhead, privacy-safe telemetry.

What is covered in this Skill?

• OpenTelemetry tracing fundamentals for Java services
• Span design: boundaries, parent/child relationships, and operation naming
• Context propagation across HTTP, messaging, async tasks, and thread boundaries
• Semantic conventions and stable attribute naming
• Error/status/event recording best practices
• Sampling strategy and performance/cost trade-offs
• Privacy and security controls for trace attributes
• Testing and verification of trace propagation and span correctness

Scope: Distributed tracing quality in application and integration layers, focused on diagnosability, consistency, and operational safety.

Constraints

Tracing instrumentation must preserve context correctly and avoid leaking sensitive data. Over-instrumentation and high-cardinality attributes can harm cost and signal quality.

• PROPAGATION FIRST: Ensure context propagation across all sync/async boundaries before adding extra span detail
• NO SENSITIVE DATA: Never store secrets, credentials, tokens, raw payloads, or PII in span attributes/events
• LOW CARDINALITY ATTRIBUTES: Avoid unbounded values in attributes that are used for aggregation/search
• VERIFY: Run ./mvnw clean verify or mvn clean verify after applying tracing changes

When to use this skill

• Improve tracing
• Apply OpenTelemetry tracing
• Add distributed tracing
• Refactor tracing instrumentation
• Instrument Java services with OpenTelemetry spans

Workflow

1. Define trace model and critical flows

Identify high-value request and async flows, define operation boundaries, and choose span names/attributes aligned with semantic conventions.

2. Instrument and propagate context

Add OpenTelemetry spans to key boundaries and ensure trace context is propagated across HTTP clients/servers, messaging, and executor-based async work.

3. Harden span data and sampling

Record status/errors/events consistently, remove sensitive data, control attribute cardinality, and configure sampling/exporters according to environment needs.

4. Validate traces end-to-end

Verify parent-child relationships, propagation continuity, and backend visibility through tests and runtime checks.

Reference

For detailed guidance, examples, and constraints, see references/183-java-observability-tracing-opentelemetry.md.