ADK Observability Guide
Scaffolded project? Cloud Trace and prompt-response logging are pre-configured by Terraform. See references/cloud-trace-and-logging.md for infrastructure details, env vars, and verification commands.
No scaffold? Follow the ADK docs links below for manual setup. For production infrastructure, scaffold with /adk-scaffold .
Reference Files
File Contents
references/cloud-trace-and-logging.md
Scaffolded project details — Terraform-provisioned resources, environment variables, verification commands, enabling/disabling locally
references/bigquery-agent-analytics.md
BQ Agent Analytics plugin — enabling, key features, GCS offloading, tool provenance
Observability Tiers
Choose the right level of observability based on your needs:
Tier What It Does Scope Default State Best For
Cloud Trace Distributed tracing — execution flow, latency, errors via OpenTelemetry spans All templates, all environments Always enabled Debugging latency, understanding agent execution flow
Prompt-Response Logging GenAI interactions exported to GCS, BigQuery, and Cloud Logging ADK agents only Disabled locally, enabled when deployed Auditing LLM interactions, compliance
BigQuery Agent Analytics Structured agent events (LLM calls, tool use, outcomes) to BigQuery ADK agents with plugin enabled Opt-in (--bq-analytics at scaffold time) Conversational analytics, custom dashboards, LLM-as-judge evals
Third-Party Integrations External observability platforms (AgentOps, Phoenix, MLflow, etc.) Any ADK agent Opt-in, per-provider setup Team collaboration, specialized visualization, prompt management
Ask the user which tier(s) they need — they can be combined. Cloud Trace is always on; the others are additive.
Cloud Trace
ADK uses OpenTelemetry to emit distributed traces. Every agent invocation produces spans that track the full execution flow.
Span Hierarchy
invocation └── agent_run (one per agent in the chain) ├── call_llm (model request/response) └── execute_tool (tool execution)
Setup by Deployment Type
Deployment Setup
Agent Engine Automatic — traces are exported to Cloud Trace by default
Cloud Run (scaffolded) Automatic — otel_to_cloud=True in the FastAPI app
GKE (scaffolded) Automatic — otel_to_cloud=True in the FastAPI app
Cloud Run / GKE (manual) Configure OpenTelemetry exporter in your app
Local dev Works with make playground ; traces visible in Cloud Console
View traces: Cloud Console → Trace → Trace explorer
For detailed setup instructions (Agent Engine CLI/SDK, Cloud Run, custom deployments), fetch https://adk.dev/integrations/cloud-trace/index.md .
Prompt-Response Logging
Captures GenAI interactions (model name, tokens, timing) and exports to GCS (JSONL), BigQuery (external tables), and Cloud Logging (dedicated bucket). Privacy-preserving by default — only metadata is logged unless explicitly configured otherwise.
Key env var: OTEL_INSTRUMENTATION_GENAI_CAPTURE_MESSAGE_CONTENT — set to NO_CONTENT (metadata only, default in deployed envs), true (full content), or false (disabled). Logging is disabled locally unless LOGS_BUCKET_NAME is set.
For scaffolded project details (Terraform resources, env vars, privacy modes, enabling/disabling, verification commands), see references/cloud-trace-and-logging.md .
For ADK logging docs (log levels, configuration, debugging), fetch https://adk.dev/observability/logging/index.md .
BigQuery Agent Analytics Plugin
Optional plugin that logs structured agent events to BigQuery. Enable with --bq-analytics at scaffold time. See references/bigquery-agent-analytics.md for details.
Third-Party Integrations
ADK supports several third-party observability platforms. Each uses OpenTelemetry or custom instrumentation to capture agent behavior.
Platform Key Differentiator Setup Complexity Self-Hosted Option
AgentOps Session replays, 2-line setup, replaces native telemetry Minimal No (SaaS)
Arize AX Commercial platform, production monitoring, evaluation dashboards Low No (SaaS)
Phoenix Open-source, custom evaluators, experiment testing Low Yes
MLflow OTel traces to MLflow Tracking Server, span tree visualization Medium (needs SQL backend) Yes
Monocle 1-call setup, VS Code Gantt chart visualizer Minimal Yes (local files)
Weave W&B platform, team collaboration, timeline views Low No (SaaS)
Freeplay Prompt management + evals + observability in one platform Low No (SaaS)
Ask the user which platform they prefer — present the trade-offs and let them choose. For setup details, fetch the relevant ADK docs page from the Deep Dive table below.
Troubleshooting
Issue Solution
No traces in Cloud Trace Verify otel_to_cloud=True in FastAPI app; check service account has cloudtrace.agent role
Prompt-response data not appearing Check LOGS_BUCKET_NAME is set; verify SA has storage.objectCreator on the bucket; check app logs for telemetry setup warnings
Privacy mode misconfigured Check OTEL_INSTRUMENTATION_GENAI_CAPTURE_MESSAGE_CONTENT value — use NO_CONTENT for metadata-only, false to disable
BigQuery Analytics not logging Verify plugin is configured in app/agent.py ; check BQ_ANALYTICS_DATASET_ID env var is set
Third-party integration not capturing spans Check provider-specific env vars (API keys, endpoints); some providers (AgentOps) replace native telemetry
Traces missing tool spans Tool execution spans appear under execute_tool — check trace explorer filters
High telemetry costs Switch to NO_CONTENT mode; reduce BigQuery retention; disable unused tiers
Deep Dive: ADK Docs (WebFetch URLs)
For detailed documentation beyond what this skill covers, fetch these pages:
Topic URL
Observability overview https://adk.dev/observability/index.md
Agent activity logging https://adk.dev/observability/logging/index.md
Cloud Trace integration https://adk.dev/integrations/cloud-trace/index.md
BigQuery Agent Analytics https://adk.dev/integrations/bigquery-agent-analytics/index.md
AgentOps https://adk.dev/integrations/agentops/index.md
Arize AX https://adk.dev/integrations/arize-ax/index.md
Phoenix (Arize) https://adk.dev/integrations/phoenix/index.md
MLflow tracing https://adk.dev/integrations/mlflow/index.md
Monocle https://adk.dev/integrations/monocle/index.md