feat: add OpenTelemetry tracing (Phase B)

[Aliciapet11]

Summary

• Add OTEL setup module (abevalflow/observability/otel.py) with lazy-init TracerProvider, env-var gating, and graceful degradation when OTEL packages not installed
• Enhance @timed_gate decorator to emit OTEL spans with gate name, duration, pass/fail, score, and mode attributes
• Apply @timed_gate to all 5 gate evaluate methods (security, quality, behavioral)
• Add OTEL span around LLM chat_completion_with_usage with model and token attributes
• Add root span in aggregate_scorecard main() wrapping full scorecard aggregation
• Add OTEL packages to Tekton task pip installs and otel-exporter-endpoint param to analyze task
• Add opentelemetry-api, opentelemetry-sdk, opentelemetry-exporter-otlp-proto-grpc to observability optional dependencies

Context

Phase B of APPENG-5370. Tracing activates only when OTEL_EXPORTER_OTLP_ENDPOINT is configured — zero overhead otherwise. Supports three modes: standalone OTEL (Jaeger/Tempo), MLflow-only tracing, or dual-export to both.

Validation

• All 1136+ tests pass (17 new OTEL tests added)
• CI ASE pipeline verified on cluster (ci-ase-otel-v2-96dnc in alicia-evalflow) — all 6 tasks succeeded
• Graceful degradation confirmed: no crashes/warnings when OTEL not configured

Test plan

• Existing tests pass (1136+)
• New OTEL setup tests (10 tests) — TracerProvider init, env var gating, graceful degradation
• New timed_gate span tests (5 tests) — span attributes, exception recording, no-op fallback
• New LLM client span tests (2 tests) — token attributes, no-op fallback
• CI ASE pipeline passes on cluster with OTEL code (no OTEL endpoint set = no-op path)
• Ruff lint/format clean

🤖 Generated with Claude Code

[GuyZivRH]

PR #69 Consolidated Review — OpenTelemetry tracing (Phase B)

PR: #69
Author: Aliciapet11 (apetruni)
Branch: feat/otel-integration → main
HEAD: 5e405c8
Size: +704 / −74 · 16 files · 2 commits
CI: SUCCESS (~50m, run 31389661392)
Ticket: APPENG-5370 Phase B
Merge state: BEHIND (slightly)
Consolidated: 2026-08-11 · prefix jzqwk_
Sources folded in: xqnlm_, lpmqx_, rptlw_, wkfnp_, xkntr_
Note: At consolidation time, Docs/commit_reviews/ only contained PR #69 reviews (earlier #57/#60/#64/#65 consolidations were no longer present).

Final verdict

Approve with minor fixes.
Consensus is Approve / Approve-with-fixes (4/5). One review (rptlw_) preferred Request changes for OTEL vs MLflow enablement inconsistency and AI co-author trailers — treat those as should-fix / clarify before treating dual mode as production, not as blockers for landing opt-in standalone OTLP on the scorecard path. CI green; design is sound.

What shipped

Lazy OpenTelemetry instrumentation (env-gated, optional deps, no-op fallback):

Piece	Role
abevalflow/observability/otel.py	Lazy TracerProvider, shutdown, _NoOpTracer
@timed_gate	Gate spans: duration, pass/fail, score, mode; exception recording
5 gates	cisco, skillmd-scanner, skillmd-quality, llm-review, edge-case
llm_client.chat_completion_with_usage	llm.chat_completion + token attrs
aggregate_scorecard.main()	Root span + setup/shutdown
Analyze Tekton task	otel-exporter-endpoint → OTEL_* env; pip install OTEL
pyproject.toml [observability]	OTEL API/SDK/OTLP gRPC
Tests	test_otel.py + LLM span tests (~17 new)
Claimed modes: standalone OTLP · MLflow-only · dual-export · neither = no-op.

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Consensus strengths

1. Opt-in / zero default overhead; ImportError → no-op.
2. Idempotent setup + finally shutdown for BatchSpanProcessor flush.
3. Useful attributes (gate outcome/score/mode; LLM model + tokens).
4. Strong unit tests (env gating, dual env flag, span attrs, exceptions, no-op).
5. CI green; author reports cluster no-op validation.
6. Optional deps correctly under observability next to mlflow (#64).

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Should fix / clarify (non-blocking for first merge)

#	Issue	Ask
1	MLflow / dual mode honesty	Docstring says “activates only when OTEL endpoint set,” but is_otel_enabled() also keys off MLFLOW_TRACKING_URI. Dual/MLflow paths set env / return without set_tracer_provider — custom get_tracer() spans may silently no-op. Document standalone-OTLP-only for these spans or init a real export path + test.
2	Setup only in aggregate_scorecard.main()	Gate/LLM export only inside that process after setup. Document Phase B scope or add setup at other entry points later.
3	Pipelines omit otel-exporter-endpoint	Wire through CI/monitoring (empty default) or document enable steps.
4	Store installs OTEL pkgs unused	Remove or justify (no setup/spans on store path).
5	LLM span	Add record_exception / ERROR status on API failure (like timed_gate).
6	Failed gates	Set non-OK span status when passed=False; guard score is not None before set_attribute.
7	gRPC URL example	http://…:4317 may be wrong for gRPC exporter (often host:4317; HTTP is :4318). Document.
8	AI co-author trailers	Co-Authored-By: Claude / PR “Generated with…” — strip per repo convention.
9	Docs	Mark Phase B done in observability plan; note env vars.
10	Scope gaps (follow-up)	Engine gates not timed; gate_results.duration_ms not written to DB; prefer gen_ai.* / policy_key naming later (#57).

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Minority stance (rptlw_)

Would Request changes until (1) OTEL/MLflow enablement is consistent and not silently no-op while advertising modes, and (2) AI co-author trailers removed. Folded above as should-fix; does not overturn Approve if Phase B is explicitly “opt-in standalone OTLP on scorecard path.”

Related work

PR	Interaction
#64 MLflow Observer	Dual-export env bridges Phase B ↔ C
#57 Join contract	Future: trace_id / run id as resource attrs
#56 Observability tables	duration_ms reserved, not populated yet

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Suggested GitHub action

1. Approve (with comments on dual-mode + pipeline wiring).
2. Ask for quick hygiene: rebase, drop AI co-author on future commits, clarify MLflow/dual in a comment or docs.
3. Follow-up PR: pipeline param, store pip trim, LLM exception spans, failed-gate status.

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Merge bar

• Env-gated no-op when unset
• Scorecard root span + shutdown
• Gate + LLM instrumentation + tests
• CI green
• (Follow-up) Dual/MLflow mode honesty or real provider init
• (Follow-up) Pipeline → analyze otel-exporter-endpoint
• Rebase on main
• (Hygiene) No AI co-author on future commits