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name: google-agents-cli-observability description: > This skill should be used when the user wants to "set up tracing", "monitor my agent", "configure logging", "add observability", "debug production traffic", or needs guidance on monitoring deployed agents, including ADK (Agent Development Kit) agents. Covers Cloud Trace, prompt-response logging, BigQuery Agent Analytics, third-party integrations (AgentOps, Phoenix, MLflow, etc.), and troubleshooting. Part of the agents-cli skills suite. Do NOT use for deployment setup (use google-agents-cli-deploy) or API code patterns (use google-agents-cli-adk-code). metadata: author: Google license: Apache-2.0 version: 1.7.0 requires: bins: - agents-cli install: "uv tool install google-agents-cli"

Observability Guide

Cloud Trace works out of the box — no infrastructure needed. Prompt-response logging and BigQuery Agent Analytics require Terraform-provisioned infrastructure (service account, GCS bucket, BigQuery dataset). Run agents-cli infra single-project --project PROJECT_ID to provision these resources. Go projects get the BigQuery telemetry stack too; the GCS completion upload behind prompt-response logging and the BigQuery Agent Analytics plugin are Python only. See references/cloud-trace-and-logging.md for details, env vars, and verification commands. If your project isn't scaffolded yet, see /google-agents-cli-scaffold first.

Order of operations for agent_runtime deployments

For deployment_target = agent_runtime, run agents-cli infra single-project before the first agents-cli deploy. The Terraform module owns the entire Reasoning Engine resource (service account, deployment spec, env vars), so applying it after an SDK-based deploy creates a state mismatch Terraform can't reconcile without taking ownership of the whole resource.

Already ran agents-cli deploy? Two options:

1. Switch to Terraform-managed — delete the SDK-deployed Reasoning Engine, then run agents-cli infra single-project and agents-cli deploy (sessions and in-flight state are lost).
2. Keep the SDK-deployed instance — skip infra single-project and set the observability env vars by re-running agents-cli deploy --update-env-vars "KEY=VALUE,..."; deploy matches the existing Reasoning Engine by display name and updates it in place, preserving env vars set outside the deploy. You must also grant its service account the telemetry IAM roles the Terraform module would otherwise provision: roles/storage.admin (write completions to the logs bucket), roles/logging.logWriter, roles/cloudtrace.agent, plus roles/bigquery.dataOwner + roles/bigquery.jobUser when scaffolded with --bq-analytics. The full set lives in deployment/terraform/single-project/iam.tf (from app_sa_roles) and telemetry.tf. Terraform-managed env vars aren't available in this mode.

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 | | references/adk-docs.md | ADK: adk.dev pages to fetch for detail beyond this skill | | references/feedback-mechanism.md | Adding a user-feedback endpoint — request model, structured logging, log sink → BigQuery |

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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 | Scaffolded ADK Python projects | Disabled locally, enabled when deployed | Auditing LLM interactions, compliance | | BigQuery Agent Analytics | Structured agent events (LLM calls, tool use, outcomes) to BigQuery | ADK Python agents with the 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 OpenTelemetry-instrumented 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.

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Cloud Trace

Scaffolded agents use OpenTelemetry to emit distributed traces. Every agent invocation produces spans that track the full execution flow.

Span Hierarchy

ADK projects. These are ADK's span names; other frameworks emit their own (generate_content comes from the shared google-genai instrumentor either way).

invoke_workflow (top-level run)
  └── invoke_agent (one per agent in the chain)
        ├── call_llm (model request)
        │     └── generate_content (underlying GenAI model call)
        └── execute_tool (tool execution)

Setup by Deployment Type

| Deployment | Setup | |-----------|-------| | Agent Runtime | Automatic — exporters wired at startup, gated on GOOGLE_CLOUD_AGENT_ENGINE_ENABLE_TELEMETRY (set by deploy); exports to Cloud Trace/Logging + Agent Engine console | | Cloud Run / GKE (scaffolded) | Automatic — exporters wired at startup, exports to Cloud Trace/Logging | | Cloud Run / GKE (manual) | Configure OpenTelemetry exporter in your app | | Local dev | Works with agents-cli playground; traces visible in Cloud Console |

Wired at app startup — ADK Python: get_fast_api_app(otel_to_cloud=True) in app/fast_api_app.py; ADK Go: setupObservability() in observability.go; other templates call their own. references/cloud-trace-and-logging.md has the details.

View traces: Cloud Console → Trace → Trace explorer

ADK: for detailed setup instructions (Agent Runtime CLI/SDK, Cloud Run, custom deployments), fetch https://adk.dev/integrations/cloud-trace/index.md.

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Prompt-Response Logging

Captures GenAI interactions and exports to GCS (JSONL) and BigQuery (via log sinks + external tables). Content is governed by two independent tiers; the net Terraform-deploy default is full content in GCS/BigQuery, none in traces:

| Tier | Captures | Controlled by | Default (Terraform deploy) | |------|----------|---------------|----------------------------| | GCS/BigQuery completions | Full prompts/responses (the prompt-response logging feature) | OTEL_INSTRUMENTATION_GENAI_COMPLETION_HOOK=upload + LOGS_BUCKET_NAME | On — full content | | Trace spans / Cloud Logging events | Span/event content | OTEL_INSTRUMENTATION_GENAI_CAPTURE_MESSAGE_CONTENT (plus ADK_CAPTURE_MESSAGE_CONTENT_IN_SPANS=false, ADK Python only) | Off — NO_CONTENT |

The tiers are independent: GCS/BigQuery uploads capture full content whenever their upload vars are set and do not honor OTEL_INSTRUMENTATION_GENAI_CAPTURE_MESSAGE_CONTENT, which governs the traces/events tier only.

ADK Python reads it as the experimental-semconv enum:

• NO_CONTENT — no content in spans/events (scaffolded default)
• EVENT_ONLY — content in Cloud Logging events
• SPAN_ONLY / SPAN_AND_EVENT — content in trace spans
• true / false — invalid; fall back to NO_CONTENT

ADK Go reads the same variable as a boolean: "1" or "true" capture content, every other value — including the enum members above — elides it.

For the full mechanics (semconv opt-in, declarative Terraform config, env-var table, 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.

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BigQuery Agent Analytics Plugin

ADK projects. Optional ADK plugin that logs structured agent events to BigQuery. Enable with --bq-analytics at scaffold time. See references/bigquery-agent-analytics.md for details.

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Third-Party Integrations

Many third-party observability platforms can ingest agent telemetry (via OpenTelemetry or custom instrumentation). The table below covers common ones; the full list is larger (see the pointer below it).

| 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. ADK: fetch a platform's setup page at https://adk.dev/integrations/<slug>/index.md (slugs for the table above: agentops, arize-ax, phoenix, mlflow-tracing, monocle, weave, freeplay); ADK has more observability integrations (Datadog, Galileo, LangWatch, Latitude, Future AGI, Respan, Zespan, …) — browse the complete, current list at https://adk.dev/integrations/ (observability topic). On other frameworks the OpenTelemetry-based platforms still work, but follow the platform's own setup docs.

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Troubleshooting

| Issue | Solution | |-------|----------| | No traces in Cloud Trace | Verify telemetry setup runs at startup and the SA has the cloudtrace.agent role. ADK Python: fast_api_app.py uses get_fast_api_app(otel_to_cloud=True); ADK Go: observability.go build the exporter manually. Agent Runtime additionally gates this on GOOGLE_CLOUD_AGENT_ENGINE_ENABLE_TELEMETRY. | | 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 | | Content in traces/events (unwanted) | ADK Python: OTEL_INSTRUMENTATION_GENAI_CAPTURE_MESSAGE_CONTENT=NO_CONTENT keeps content out of spans/events. ADK Go: any value other than 1/true does, so unset it or set false. NOTE: GCS/BigQuery completions still capture full content — to stop that, remove LOGS_BUCKET_NAME/OTEL_INSTRUMENTATION_GENAI_COMPLETION_HOOK (drop the upload block in service.tf) | | BigQuery Analytics not logging | ADK Python: verify the 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 | ADK: tool execution spans appear under execute_tool (other frameworks use their own span names) — check trace explorer filters | | High telemetry costs | Turn content capture off (NO_CONTENT in Python, false in Go); reduce BigQuery retention; disable unused tiers |

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Related Skills

• /google-agents-cli-deploy — Deployment targets, CI/CD pipelines, and production workflows
• /google-agents-cli-workflow — Development workflow, coding guidelines, and operational rules
• /google-agents-cli-adk-code — ADK API quick reference for writing agent code, Python and Go