Claude Skill: Backblaze B2 Cloud Storage Manager

A Claude Code skill for managing Backblaze B2 cloud storage directly from your terminal — list files, audit buckets, clean up stale data, and review security posture.

Built on the open Agent Skills specification. Compatible with Claude Code, Codex CLI, Cursor, Gemini CLI, and other skills-compatible agents.

Features

• List & search objects across buckets with prefix filtering
• Storage audit — live vs. billable storage, breakdown by prefix + extension, configurable thresholds
• Hidden-cost detection — surfaces unfinished large uploads, old versions, and hide markers that still bill
• Cost estimation — monthly storage cost + potential savings after cleanup
• Duplicate detection — groups files by contentSha1 (true duplicates, not same-name)
• Stale & large-file flags — configurable --stale-days and --large-mb thresholds
• JSON output — --json flag for downstream analysis
• Cleanup with safety — mandatory dry-run + explicit "yes" confirmation before any deletion
• Security review — per-bucket checklist (type, SSE, CORS, object lock, replication, lifecycle coverage)
• Lifecycle rules — view and update expiration policies
• Guided setup — walks through CLI install, app-key creation, and authorization
• Per-project config — different buckets and credentials per project

Install

One-liner

git clone https://github.com/backblaze-labs/claude-skill-b2-cloud-storage.git /tmp/b2-skill && cp -r /tmp/b2-skill/b2-cloud-storage ~/.claude/skills/b2-cloud-storage && rm -rf /tmp/b2-skill

Manual

cp -r b2-cloud-storage ~/.claude/skills/b2-cloud-storage

Verify

ls ~/.claude/skills/b2-cloud-storage/SKILL.md

Usage

The skill is auto-invoked when you mention B2 in natural language, or you can call it explicitly with /b2-cloud-storage:

> help me set up B2

> list everything in my-bucket

> audit my-bucket for stale files, duplicates, and unfinished uploads

> clean up files older than 90 days in my-bucket/logs

> run a security review on my public buckets

The audit script can also be run directly:

python ~/.claude/skills/b2-cloud-storage/scripts/storage_audit.py <bucket>
python ~/.claude/skills/b2-cloud-storage/scripts/storage_audit.py <bucket> --json
python ~/.claude/skills/b2-cloud-storage/scripts/storage_audit.py <bucket> \
  --stale-days 180 --large-mb 500 --prefix-depth 2

Note: You may need to restart Claude Code after installing the skill for it to be recognized.

Setup & API Keys

The skill handles setup automatically on first use:

1. Installs B2 CLI if not found (pip install b2)
2. Checks authorization — skips ahead if already configured
3. Guides API key creation:
   • Log in at secure.backblaze.com
   • Go to App Keys > Add a New Application Key
   • Set permissions (listBuckets, listFiles, readFiles for read-only)
   • Copy the keyID and applicationKey
4. Authorizes the CLI — runs b2 account authorize interactively (keys stay in your terminal, never in chat)
5. Verifies access with b2 ls

Credentials are stored by the B2 CLI in ~/.b2_account_info. The skill never sees or stores your keys.

Per-Project Configuration

Different projects can use different B2 buckets and credentials. On first use in a project, the skill asks which bucket to use and saves a config file at .claude/b2-config.json in your project root:

{
  "bucket": "my-project-bucket",
  "prefix": "",
  "accountInfoPath": "~/.b2_account_info"
}

To use separate credentials per project, authorize into a project-specific file:

B2_ACCOUNT_INFO=~/.b2_account_info_myproject b2 account authorize

Then set accountInfoPath to ~/.b2_account_info_myproject in your project's config.

An example config file is included at b2-cloud-storage/b2-config.example.json.

Note: This config file stores bucket names and file paths only — never API keys or secrets. Add .claude/b2-config.json to your .gitignore.

Security

• b2 account get and b2 key * commands are blocked (credential exposure)
• All deletions require --dry-run preview + explicit "yes" confirmation
• Bucket visibility changes (allPublic) require warning + confirmation
• All operations default to read-only
• API keys are never stored or displayed by the skill
• If you accidentally paste keys into chat, the skill warns you to rotate them

File Structure

claude-skill-b2-cloud-storage/
├── README.md
├── .github/workflows/ci.yml             # Lint + tests + frontmatter validation
├── tests/                               # Unit tests for the audit script
└── b2-cloud-storage/                    # Copy this folder to ~/.claude/skills/
    ├── SKILL.md                         # Skill definition and instructions
    ├── b2-config.example.json           # Example per-project config
    ├── scripts/
    │   └── storage_audit.py             # Audit: usage, versions, unfinished, cost
    └── references/
        ├── setup.md                     # First-use setup walk-through
        ├── cleanup-playbook.md          # Safe deletion procedure
        ├── security-review.md           # Per-bucket security checklist
        └── b2-cli-reference.md          # B2 CLI v4 command reference

Requirements

• Claude Code (or any Agent Skills-compatible tool)
• Python 3.9+
• B2 CLI v4+ (auto-installed by the skill)
• A Backblaze B2 account

License

MIT