ADK Development Workflow & Guidelines STOP — Do NOT write code yet. If no project exists, scaffold first with agents-cli scaffold create . If the user already has code, use agents-cli scaffold enhance . to add the agents-cli structure. Run agents-cli info to check if a project already exists. Skipping this leads to missing eval boilerplate, CI/CD config, and project conventions. agents-cli is a CLI and skills toolkit for building, evaluating, and deploying agents on Google Cloud using the Agent Development Kit (ADK) . It works with any coding agent — Gemini CLI, Claude Code, Codex, or others. Install with uvx google-agents-cli setup . Requires: google-agents-cli = 0.1.0 If version is behind, run: uv tool install "google-agents-cli =0.1.0" Check version: agents-cli info Install uv first if needed. Session Continuity & Skill Cross-References Re-read the relevant skill before each phase — not after you've already started and hit a problem. Context compaction may have dropped earlier skill content. If skills are not available, run uvx google-agents-cli setup to install them. Phase Skill When to load 0 — Understand — No skill needed — read DESIGN_SPEC.md or clarify goals with the user 1 — Study samples — Check Notable Samples table below — clone and study matching samples before scaffolding 2 — Scaffold /google-agents-cli-scaffold Before creating or enhancing a project 3 — Build /google-agents-cli-adk-code Before writing agent code — API patterns, tools, callbacks, state 4 — Evaluate /google-agents-cli-eval Before running any eval — evalset schema, metrics, eval-fix loop 5 — Deploy /google-agents-cli-deploy Before deploying — target selection, troubleshooting 403/timeouts 6 — Publish /google-agents-cli-publish After deploying, if registering with Gemini Enterprise (optional) 7 — Observe /google-agents-cli-observability After deploying — traces, logging, monitoring setup Setup If agents-cli is not installed: uv tool install google-agents-cli uv command not found Install uv following the official installation guide . Product name mapping The platform formerly known as "Vertex AI" is now Gemini Enterprise Agent Platform (short: Agent Platform ). Users may refer to products by different names. Map them to the correct CLI values: User may say CLI value Agent Engine, Vertex AI Agent Engine, Agent Runtime --deployment-target agent_runtime Vertex AI Search, Agent Search --datastore agent_platform_search Vertex AI Vector Search, Vector Search --datastore agent_platform_vector_search Agent Engine sessions, Agent Platform Sessions --session-type agent_platform_sessions The vertexai Python SDK package name is unchanged. Phase 0: Understand Before writing or scaffolding anything, understand what you're building. If DESIGN_SPEC.md already exists, read it — it is your primary source of truth. Otherwise: Do NOT proceed to planning, scaffolding, or coding. Ask the user the questions below and wait for their answers. You MUST have the user's answers before moving on. Do not assume, research, or fill in the blanks yourself. The user's intent drives everything — skipping this step leads to wasted work. Always ask: What problem will the agent solve? — Core purpose and capabilities External APIs or data sources needed? — Tools, integrations, auth requirements Safety constraints? — What the agent must NOT do, guardrails Deployment preference? — Prototype first (recommended) or full deployment? If deploying: Agent Runtime, Cloud Run, or GKE? Ask based on context: If retrieval or search over data mentioned (RAG, semantic search, vector search, embeddings, similarity search, data ingestion) → Datastore? Options: agent_platform_vector_search (embeddings, similarity search) or agent_platform_search (document search, search engine). If agent should be available to other agents → A2A protocol? Enables the agent as an A2A-compatible service. If full deployment chosen → CI/CD runner? GitHub Actions (default) or Google Cloud Build? If agent should remember user preferences or facts across sessions → Memory Bank? Long-term memory across conversations. See /google-agents-cli-adk-code . If Cloud Run or GKE chosen → Session storage? In-memory (default), Cloud SQL (persistent), or Agent Platform Sessions (managed). If deployment with CI/CD chosen → Git repository? Does one already exist, or should one be created? If creating, public or private? Once you have the user's answers, write a DESIGN_SPEC.md with the user's approval. See /google-agents-cli-scaffold for how these choices map to CLI flags. At minimum include these sections — expand with more detail if the user wants a thorough spec:

DESIGN_SPEC.md

Overview Describe the agent's purpose and how it works.

Example Use Cases Concrete examples with expected inputs and outputs.

Tools Required Each tool with its purpose, API details, and authentication needs.

Constraints & Safety Rules Specific rules — not just generic statements.

Success Criteria Measurable outcomes for evaluation.

Reference Samples Check the Notable Samples in Phase 1 — list any that match this use case. Optional sections for more detailed specs: Edge Cases to Handle , Architecture & Sub-Agents , Data Sources & Auth , Non-Functional Requirements . Once you have a clear understanding, proceed to Phase 1 . Phase 1: Study Reference Samples Ask yourself: is there a sample that can help me design this and cut time? Scan the keywords below. Multiple samples can match — clone and study all that are relevant.

Clone a sample to study — read the key files, understand the patterns, then apply

them to your own scaffolded project. Do NOT use adk@<sample> scaffolding.

git

clone

--filter

=

tree:0

--sparse

https://github.com/google/adk-samples /tmp/adk-samples

2

>

/dev/null

;

\

cd

/tmp/adk-samples

&&

git

sparse-checkout

add

python/agents/

<

sample-name

>

ambient-expense-agent

— Agent that runs on a schedule or reacts to events, with no interactive user.

Keywords: scheduled, cron, daily, pubsub, event-driven, alerts, email, ambient

Key files:

expense_agent/fast_api_app.py

,

expense_agent/agent.py

,

expense_agent/config.py

,

terraform/

adk-ae-oauth

— Agent with OAuth 2.0 user consent, deployed to Agent Runtime with Gemini Enterprise.

Keywords: OAuth, authentication, user consent, Google Drive, Agent Runtime, Gemini Enterprise

Key files:

README.md

,

adk_ae_oauth/tools.py

,

adk_ae_oauth/auths.py

genmedia-for-commerce

— Full-stack agent with React UI, MCP tools, media/image handling, and Gemini Enterprise registration.

Keywords: MCP, media, video generation, Veo, virtual try-on, retail, full-stack, React, Gemini Enterprise

Key files:

genmedia4commerce/agent.py

,

genmedia4commerce/agent_utils.py

,

genmedia4commerce/fast_api_app.py

deep-search

— Research agent that iterates until quality is met, with source citations.

Keywords: research, citations, iterative, grounding, multi-agent, human-in-the-loop, web search, report

Key files:

app/agent.py

,

app/config.py

safety-plugins

— Reusable safety guardrails that plug into any agent runner.

Keywords: safety, guardrails, model armor, filters

Key files:

safety_plugins/plugins/model_armor.py

,

safety_plugins/plugins/agent_as_a_judge.py

,

safety_plugins/main.py

data-science

— Agent that executes code in a managed sandbox for data analysis.

Keywords: SQL, BigQuery, code execution, sandbox

Key files:

data_science/sub_agents/analytics/agent.py

memory-bank

— Conversational agent with cross-session memory via Memory Bank (Cloud Run and Agent Runtime).

Keywords: memory, cross-session, recall, context, remember, Memory Bank

Key files:

app/agent.py

,

app/agent_runtime_app.py

,

app/fast_api_app.py

If no sample matches, proceed to Phase 2. But first — are you sure? Re-read the user's request and compare it against the keywords above. Skipping a matching sample means rebuilding patterns that already exist.

IMPORTANT — Exit criteria:

After studying a sample, ask yourself: can I apply anything from this sample to help me deliver the design? Note what you'll reuse before moving on. Do NOT proceed until you've answered this.

This list is useful at any phase

— revisit it when you hit deployment, publishing, or infrastructure questions. A sample's Terraform or registration pattern may be exactly what you need later.

Phase 2: Scaffold (if needed)

Use

/google-agents-cli-scaffold

to create a new project or import an existing one into the agents-cli format (adding deployment, CI/CD, infrastructure). It covers architecture choices (deployment target, agent type, session storage) and project creation or enhancement.

Skip this phase if the project was already created or enhanced by agents-cli — run

agents-cli info

from the project root to check.

Phase 3: Build and Implement

Implement the agent logic:

Write/modify code in the agent directory (check

GEMINI.md

/

CLAUDE.md

for directory name)

Quick smoke test

Use

agents-cli run "your prompt"

to verify the agent works after changes — this is the fastest way to check behavior without leaving the terminal

Iterate on the implementation based on user feedback

If the user asks for interactive testing, suggest

agents-cli playground

— it opens a web-based playground for manual conversation with the agent.

For ADK API patterns and code examples, use

/google-agents-cli-adk-code

.

NEVER write pytest tests that assert on LLM output content

(e.g., checking for keywords in responses, verifying persona, validating tone). LLM outputs are non-deterministic — these tests are flaky by nature and belong in eval, not pytest. Use

agents-cli run

for quick checks and

agents-cli eval run

for systematic validation.

Phase 3.5: Provision Datastore (RAG projects only)

For

agentic_rag

projects, provision the datastore before testing:

agents-cli infra datastore

, then

agents-cli data-ingestion

. Use

infra datastore

—

not

infra single-project

(same datastore provisioning but faster, skips unrelated Terraform).

Phase 4: Evaluate

This is the most important phase.

Evaluation validates agent behavior end-to-end.

MANDATORY:

Activate

/google-agents-cli-eval

before running evaluation.

It contains the evalset schema, config format, and critical gotchas. Do NOT skip this.

Do NOT skip this phase.

After building the agent, you MUST proceed to evaluation. Do NOT write pytest tests to validate agent behavior — that is what eval is for.

uv run pytest

vs

agents-cli eval run

— know the difference:

uv run pytest

— Tests

code correctness

imports work, functions return expected types, API contracts hold. Does NOT test whether the agent behaves well.

agents-cli eval run

— Tests

agent behavior

response quality, tool usage, persona consistency, safety compliance. This is what validates your agent actually works.

agents-cli run "prompt"

— Quick one-off smoke test during development. Use this for fast iteration, not pytest.

NEVER write pytest tests that check LLM response content

(e.g., asserting pirate keywords appear, checking if the agent mentions allergies). LLM outputs are non-deterministic. Use eval with LLM-as-judge criteria instead.

Start small

Begin with 1-2 sample eval cases, not a full suite

Run evaluations:

agents-cli eval run

Discuss results with the user

Fix issues and iterate on the core cases first

Only after core cases pass, add edge cases and new scenarios

Repeat until quality thresholds are met

Expect 5-10+ iterations here.

Phase 5: Deploy

Once evaluation thresholds are met:

Check if the project has a deployment target configured — run

agents-cli info

to see current config

If the project is a prototype (no deployment target), add deployment support first:

agents-cli scaffold enhance

.

--deployment-target

<

target

>

See

/google-agents-cli-deploy

for the deployment target decision matrix (Agent Runtime vs Cloud Run vs GKE).

Deploy when ready:

agents-cli deploy

IMPORTANT

Never deploy without explicit human approval. Phase 6: Publish (optional) Not all agents require this — currently supporting Gemini Enterprise. See /google-agents-cli-publish for registration modes, flags, and troubleshooting. Phase 7: Observe After deploying, use observability tools to monitor agent behavior in production. See /google-agents-cli-observability for Cloud Trace, prompt-response logging, BigQuery Analytics, and third-party integrations. Operational Guidelines for Coding Agents Common Shortcuts to Resist Agents routinely skip steps with plausible-sounding excuses. Recognize these and push back: Shortcut Why it fails "The user's request is clear enough, no need to clarify" You're guessing at requirements. Phase 0 exists to confirm intent before scaffolding — even one question can prevent a full rework. "The agent responded correctly in agents-cli run , so eval isn't needed" One prompt is not a test suite. Eval catches regressions, edge cases, and tool trajectory issues that a single run never will. "I'll use a newer/better model" The scaffolded model was chosen deliberately. Changing it without being asked violates code preservation (Principle 1) and often breaks things — wrong location, deprecated version, or 404. Your training data is likely out of date — rely on the skills and the model listing command, not your knowledge of model names. "I can skip the scaffold and set up manually" Manual setup misses eval boilerplate, CI/CD config, and pyproject.toml conventions. Use agents-cli create even for quick experiments. Principle 1: Code Preservation & Isolation Code modifications require surgical precision — alter only the code segments directly targeted by the user's request and strictly preserve all surrounding and unrelated code. Mandatory Pre-Execution Verification: Before finalizing any code replacement, verify the following: Target Identification: Clearly define the exact lines or expressions to change, based solely on the user's explicit instructions. Preservation Check: Confirm that all code, configuration values (e.g., model , version , api_key ), comments, and formatting outside the identified target remain identical. Example: User Request: "Change the agent's instruction to be a recipe suggester." Incorrect (VIOLATION): root_agent = Agent ( name = "recipe_suggester" , model = "gemini-1.5-flash" ,

UNINTENDED - model was not requested to change

instruction

"You are a recipe suggester." ) Correct (COMPLIANT): root_agent = Agent ( name = "recipe_suggester" ,

OK, related to new purpose

model

"gemini-flash-latest" ,

PRESERVED

instruction

"You are a recipe suggester."

OK, the direct target

) Principle 2: Execution Best Practices Model Selection — CRITICAL: NEVER change the model unless explicitly asked. When creating NEW agents (not modifying existing), use the latest Gemini model. List available models to pick the newest one:

Use 'global' or any supported region (e.g. 'us-east1')

uv run

--with

google-genai python

-c

"

from google import genai

client = genai.Client(vertexai=True, location='global')

for m in client.models.list(): print(m.name)

"

Do NOT use older models unless explicitly requested. For model docs, fetch

https://adk.dev/agents/models/google-gemini/index.md

. See also

stable model versions

.

Running Python Commands:

Always use

uv

to execute Python commands (e.g.,

uv run python script.py

)

Run

uv sync

before executing scripts

Breaking Infinite Loops:

Stop immediately

if you see the same error 3+ times in a row

RED FLAGS

Lock IDs incrementing, names appending v5→v6→v7, "I'll try one more time" repeatedly

State conflicts

(Error 409): Use

terraform import

instead of retrying creation

When stuck

Run underlying commands directly (e.g., terraform CLI) Troubleshooting: Check /google-agents-cli-adk-code first — it covers most common patterns Use WebFetch on URLs from the ADK docs index ( curl https://adk.dev/llms.txt ) for deep dives When encountering persistent errors, a targeted web search often finds solutions faster CLI command failures: run agents-cli --help — the output ends with a Source: line pointing to the exact source file implementing that command. Read it to understand the logic and diagnose failures. Use agents-cli info to get the full CLI install path if you need to browse across multiple files. Systematic Debugging When something breaks, follow this sequence — don't skip steps or shotgun fixes: Reproduce — Run the exact command that failed. Save the full error output. If you can't reproduce it, you can't fix it. Localize — Narrow the cause: is it the agent code, a tool, the config, or the environment? Use agents-cli run "prompt" to isolate agent behavior from deployment issues. Fix one thing — Change one variable at a time. If you change the instruction AND the tool AND the config simultaneously, you won't know what fixed it (or what broke something else). Verify — Rerun the exact reproduction command. Don't assume the fix worked. Guard — If it was a non-obvious bug, add an eval case to catch regressions. Stop-the-line rule: If a change breaks something that was working, stop feature work and fix the regression first. Don't push forward hoping to circle back — regressions compound. Environment Variables: .env files and env var assignments (e.g., GOOGLE_CLOUD_PROJECT , GOOGLE_CLOUD_LOCATION ) are typically required for the agent to function — never remove or modify them unless the user explicitly asks If a .env file exists in the project root, treat it as essential configuration For secrets and API keys, prefer GCP Secret Manager over plain .env entries — see /google-agents-cli-deploy for secret management guidance Using a Temporary Scaffold as Reference When you need specific infrastructure files (Terraform, CI/CD, Dockerfile) but don't want to modify the current project, use /google-agents-cli-scaffold to create a temporary project in /tmp/ and copy over what you need. Reference Files File Contents references/internals.md Underlying tools and commands that agents-cli wraps (adk, pytest, ruff, uvicorn) Development Commands Setup & Skills Command Purpose agents-cli setup Install skills to coding agents agents-cli setup --skip-auth Install skills, skip authentication step agents-cli setup --dry-run Preview what setup would do without executing agents-cli update Reinstall/update skills to latest version Scaffolding Command Purpose agents-cli scaffold create Create a new project agents-cli scaffold enhance . Add deployment / CI-CD to project agents-cli scaffold upgrade Upgrade project to newer agents-cli version Development Command Purpose agents-cli playground Interactive local testing (ADK web playground) agents-cli run "prompt" Run agent with a single prompt (non-interactive) agents-cli lint Check code quality agents-cli lint --fix Auto-fix linting issues agents-cli lint --mypy Also run mypy type checking agents-cli install Install project dependencies (uv sync) Evaluation Command Purpose agents-cli eval run Run evaluation against evalsets agents-cli eval run --evalset F Run a specific evalset agents-cli eval run --all Run all evalsets agents-cli eval compare BASE CAND Compare two eval result files Deployment & Infrastructure Command Purpose agents-cli deploy Deploy to dev (requires human approval) agents-cli infra single-project Provision single-project GCP infrastructure without CI/CD (Terraform, optional) agents-cli infra cicd Set up CI/CD pipeline + staging/prod infrastructure agents-cli publish gemini-enterprise Register agent with Gemini Enterprise Project Info Command Purpose agents-cli info Show CLI install path, skills location, and project config Use agents-cli info to discover the CLI install path — this is where the CLI source code lives. Read files under that path to understand CLI internals, command implementations, or template logic. The command only shows project details when run inside a generated agent project (i.e., one with [tool.agents-cli] in pyproject.toml ). Authentication Command Purpose agents-cli login --interactive Authenticate with Google for ADK services ( -i / --interactive is required for interactive browser-based authentication) agents-cli login --status Show authentication status [!NOTE] When using an API key to authenticate, the login command does not persist them automatically, it just aids in retrieving them and providing instructions on how they can be persisted. Skills Version Troubleshooting hint: If skills seem outdated or incomplete, reinstall: agents-cli setup --skip-auth Only do this when you suspect stale skills are causing problems.