gcs-security-assessment

gcs-security-assessment is a skill for Claude Code, Codex from gemini-cli-extensions/google-cloud-storage. It costs 181 tokens per session (1,506 once invoked), scanned A, a copy of gcs-security-assessment, Apache-2.0.

A review tool for assessing the security of Google Cloud Storage, Google's service for storing files in cloud buckets. It checks gathered configuration and activity signals against Google's security guidance.

In plain words
What is it for?
Use it to review bucket and project access, encryption, network protections, audit logging, and related security risks, then produce remediation guidance.
Why use it?
It can reveal exposed buckets, overly broad access, missing encryption or logging, and risky combinations of settings without assuming facts that were not checked.

Skill for Claude CodeCodex

Part of the google-cloud-storage plugin — 5 skills, 1 MCP server shipped together

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/gemini-cli-extensions/google-cloud-storage/gcs-security-assessment
Any agent
npx skills add gemini-cli-extensions/google-cloud-storage --skill gcs-security-assessment
Clone the repo
git clone --depth 1 https://github.com/gemini-cli-extensions/google-cloud-storage

Made for: Claude Code, Codex.

Or install google-cloud-storage, the plugin that ships this one along with the rest of its 5 skills, 1 MCP server.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for gcs-security-assessment

README.md
[![agentmods](https://agentmods.dev/badge/skills/gemini-cli-extensions/google-cloud-storage/gcs-security-assessment.svg)](https://agentmods.dev/skills/gemini-cli-extensions/google-cloud-storage/gcs-security-assessment)
Your own site
<a href="https://agentmods.dev/skills/gemini-cli-extensions/google-cloud-storage/gcs-security-assessment"><img src="https://agentmods.dev/badge/skills/gemini-cli-extensions/google-cloud-storage/gcs-security-assessment.svg" alt="Measured on agentmods" height="20"></a>
Per session 181 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,506 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin 89% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00181 $0.01506
Opus 5 $0.00090 $0.00753
Sonnet 5 $0.00036 $0.00301
Haiku 4.5 $0.00018 $0.00151

Measured 5d ago against content hash 401e68c870b8, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

gcs-security-assessment scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 5d ago.

The scan reads SKILL.md. This mod also ships 7 executable files (scripts/cloud_rest_helpers_nodeps.py, scripts/evaluate_project_security_posture.py, scripts/fetch_bucket_telemetry.py, …), listed below but not scanned — reading those needs a real analyzer, not pattern matching.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

89% identical to gcs-security-assessment — 2 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

skills/gcs-security-assessment/SKILL.md · 104 lines

How it starts

The opening of the file, as written. The whole thing — 104 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Security Posture Assessment Skill

You are a Google Cloud Storage security assessment agent trained on Google's Secure AI Framework (SAIF). Your job is to evaluate GCS bucket and project configurations, identify toxic combinations of vulnerabilities, and provide actionable remediation.

[!IMPORTANT]

You are NOT a generic security chatbot. You MUST ground every finding in telemetry signals you have actually gathered. NEVER hallucinate findings or assume configurations you have not verified. If you cannot gather a signal, say so explicitly and skip that check.

[!CAUTION]

CRITICAL: Never execute destructive commands (e.g., rm, rb, IAM policy changes) without first printing the exact command and explicitly asking the user for a Y/N confirmation.

Philosophy

Traditional security tools generate isolated alerts from static rules (e.g., "bucket is public"). You correlate multiple signals to detect toxic combinations — scenarios where individually low-risk configurations combine to create critical exposures. A public bucket storing marketing PDFs is very different from a public bucket storing ML training data with no CMEK, no VPC-SC, and no audit logging.

Phase Summary Table

Phase Inputs Outputs Reference
1. Discover Scope & Telemetry User input (Project ID/Buckets/Datasets) Scope confirmation, Telemetry signals references/phases/discover.md
2. Bucket Classification Telemetry signals Bucket classifications references/phases/classification.md
3. Baseline Security Eval Telemetry signals, Classifications Baseline failures references/phases/baseline.md
4. Toxic Combo Analysis Telemetry signals, Classifications Toxic combination findings references/phases/toxic_analysis.md
5. Output Findings from all phases Formatted assessment report references/phases/output.md

Read the full file on GitHub · 104 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 5d ago First seen · 104 lines · 181 tokens per session scan A 401e68c870b8

Subscribe to this mod's changes

gcs-security-assessment is a skill published in the GitHub repository gemini-cli-extensions/google-cloud-storage (25 stars, last pushed 4d ago), licensed Apache-2.0. It adds 181 tokens to every session and 1,506 once invoked, about $0.0009 per session on Opus 5. A static security scan graded it A with 0 findings. It is 89% identical to gcs-security-assessment, differing in 2 lines, and is treated as a copy.