Google Agents CLI Publish Agent Skill

Gemini Enterprise Registration

> Requires: A deployed agent. For Agent Runtime, deployment_metadata.json (created by agents-cli deploy) enables auto-detection. For Cloud Run or GKE, provide the agent card URL and flags directly.

Prerequisites

• Agent must be deployed — the agent must be running and reachable
• Gemini Enterprise app must exist — Create one in Google Cloud Console → Gemini Enterprise → Apps before registering
• deployment_metadata.json (Agent Runtime only) — Created automatically by agents-cli deploy; contains the agent runtime ID, deployment target, the A2A flag, and the agent directory

Required Permissions for A2A on Cloud Run

• roles/run.servicesInvoker granted to the Discovery Engine service account (service-<PROJECT_NUMBER>@gcp-sa-discoveryengine.iam.gserviceaccount.com) on the Cloud Run service.

Registration Modes

A2A Registration (Cloud Run / GKE)

Every scaffolded agent serves the Agent-to-Agent protocol. A2A is the default — and only — registration type on Cloud Run and GKE, which have no reasoning engine, so Gemini Enterprise registers them over A2A. Pass the agent card URL and the command fetches the card and registers it; display name and description default to the card's name/description.

# A2A on Cloud Run / GKE
agents-cli publish gemini-enterprise \
  --agent-card-url https://my-service-abc123.us-east1.run.app/a2a/app/.well-known/agent-card.json \
  --gemini-enterprise-app-id projects/123456/locations/global/collections/default_collection/engines/my-app

Pass --display-name / --description to override the card defaults. For Agent Runtime, use ADK registration (below).

ADK Registration (default on Agent Runtime)

This is the default and recommended registration for Agent Runtime deployments: Gemini Enterprise invokes the agent natively via :streamQuery on its reasoning engine resource, authenticating end-to-end. Under the hood, :streamQuery dispatches to the AdkApp's streaming_agent_run_with_events method — when debugging an ADK invocation, search the runtime's reasoning_engine_stderr logs for that method name to trace the failure. It's also the path to use when the agent needs an OAuth authorization (--authorization-id). The agent is registered directly via its reasoning engine resource name; no agent card URL is needed.

agents-cli publish gemini-enterprise \
  --registration-type adk \
  --agent-runtime-id projects/123456/locations/us-east1/reasoningEngines/789 \
  --gemini-enterprise-app-id projects/123456/locations/global/collections/default_collection/engines/my-app \
  --display-name "My Agent" \
  --description "Handles customer queries" \
  --tool-description "Answers questions about products"

Programmatic Mode (CI/CD)

The command is non-interactive by default — pass all required values via flags or environment variables. This makes it safe for CI/CD pipelines.

Via flags

agents-cli publish gemini-enterprise \
  --agent-runtime-id "$AGENT_RUNTIME_ID" \
  --gemini-enterprise-app-id "$GEMINI_ENTERPRISE_APP_ID" \
  --display-name "Production Agent" \
  --registration-type adk

Via environment variables

Most flags have an env var alternative (--metadata-file, --interactive, and --list do not):

export AGENT_RUNTIME_ID="projects/123456/locations/us-east1/reasoningEngines/789"
export GEMINI_ENTERPRISE_APP_ID="projects/123456/locations/global/collections/default_collection/engines/my-app"
export GEMINI_DISPLAY_NAME="Production Agent"
export GEMINI_DESCRIPTION="Handles customer queries"

agents-cli publish gemini-enterprise

Interactive Mode (--interactive)

Pass --interactive (or -i) to be guided through any missing values with interactive prompts. The command will list available Gemini Enterprise apps, offer to auto-detect the agent runtime ID from metadata, and prompt for display name and description.

agents-cli publish gemini-enterprise --interactive

Complete Flag Reference

| Flag | Env Var | Description |

|------|---------|-------------|

| --agent-runtime-id | AGENT_RUNTIME_ID | Agent Runtime resource name (auto-detected from deployment_metadata.json) |

| --gemini-enterprise-app-id | ID or GEMINI_ENTERPRISE_APP_ID | Gemini Enterprise app full resource name |

| --display-name | GEMINI_DISPLAY_NAME | Display name in Gemini Enterprise |

| --description | GEMINI_DESCRIPTION | Agent description |

| --tool-description | GEMINI_TOOL_DESCRIPTION | Tool description (ADK mode only, defaults to description) |

| --registration-type | REGISTRATION_TYPE | adk or a2a (defaults to adk on Agent Runtime, a2a on Cloud Run / GKE) |

| --agent-card-url | AGENT_CARD_URL | Agent card URL for A2A registration |

| --deployment-target | DEPLOYMENT_TARGET | agent_runtime, cloud_run, or gke (sets the default registration type — ADK on Agent Runtime, A2A on Cloud Run / GKE — and the A2A auth method) |

| --project-id | GOOGLE_CLOUD_PROJECT | GCP project ID for billing |

| --project-number | PROJECT_NUMBER | GCP project number (used for Gemini Enterprise lookup) |

| --authorization-id | GEMINI_AUTHORIZATION_ID | OAuth authorization resource name |

| --metadata-file | — | Path to deployment metadata (default: deployment_metadata.json) |

| --interactive / -i | — | Enable interactive prompts |

| --list | — | List Gemini Enterprise apps in the current project and exit |

Auto-Detection from Metadata

When deployment_metadata.json exists, the command automatically:

• Reads the agent runtime ID (remote_agent_runtime_id)
• Determines the registration type: defaults to ADK (native :streamQuery) on Agent Runtime, and A2A on Cloud Run / GKE (which have no reasoning engine). Override with --registration-type.
• Determines the deployment target for authentication

This means that for the simplest case (an agent on Agent Runtime, registered as ADK), you only need to provide the Gemini Enterprise app ID:

agents-cli publish gemini-enterprise \
  --gemini-enterprise-app-id projects/123456/locations/global/collections/default_collection/engines/my-app

SDK Compatibility

Agent Runtime deployments may encounter "Session not found" errors with google-cloud-aiplatform versions <= 1.128.0. In interactive mode (--interactive), the command checks the SDK version from uv.lock and offers to upgrade. In programmatic mode, ensure your SDK is up to date before registering.

Managing Agents in Agent Registry

Agent Registry (Preview) is the Google Cloud fleet-wide record of your agents.

Agents deployed to a managed runtime (Agent Runtime on Gemini Enterprise

Agent Platform) are auto-registered — no extra step after agents-cli deploy.

Manage them with gcloud (requires roles/agentregistry.editor):

# List / filter
gcloud alpha agent-registry agents list --project PROJECT --location LOCATION
gcloud alpha agent-registry agents list --filter="displayName:my-agent"

# Inspect
gcloud alpha agent-registry agents describe AGENT_NAME

# Update endpoint/metadata — edit the Service resource, not the Agent
gcloud alpha agent-registry services update AGENT_NAME \
  --display-name "..." --description "..." \
  --interfaces "url=ENDPOINT_URL,protocol=HTTP_JSON"

# Remove: delete the underlying runtime agent (auto-registered) OR, for
# manually registered agents, delete the Service resource
gcloud alpha agent-registry services delete AGENT_NAME

Docs: https://docs.cloud.google.com/agent-registry/manage-agents

Troubleshooting

| Issue | Solution |

|-------|----------|

| "Session not found" after registration | SDK version issue — upgrade google-cloud-aiplatform (see SDK Compatibility above), redeploy, then re-register |

| --registration-type is required | Non-interactive mode needs --registration-type when no deployment_metadata.json exists |

| "Gemini Enterprise App ID is required" | Provide --gemini-enterprise-app-id or set the ID / GEMINI_ENTERPRISE_APP_ID env var |

| Re-publishing the same agent | Registration is idempotent — re-running updates the existing registration in place instead of creating a duplicate |

| HTTP 403 on registration | Check that your account has Discovery Engine Editor permissions on the Gemini Enterprise project |

| Debugging ADK invocation failures on Agent Runtime | Gemini Enterprise calls the agent via the AdkApp's streaming_agent_run_with_events method (the native :streamQuery contract). Grep the runtime's reasoning_engine_stderr logs for streaming_agent_run_with_events to find the underlying error |

| "Could not fetch agent card" | Verify the agent is running and the URL is correct; for Cloud Run, ensure gcloud auth login is done |

Related Skills

• /google-agents-cli-deploy — Deployment targets, CI/CD pipelines, and production workflows (also covers Agent Gateway governed ingress/egress and Semantic Governance awareness)
• /google-agents-cli-workflow — Development workflow, coding guidelines, and operational rules
• /google-agents-cli-scaffold — Project creation and enhancement with agents-cli scaffold create / scaffold enhance