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.
npx skills add 0xDarkMatter/claude-mods --skill leveldb-opsgit clone --depth 1 https://github.com/0xDarkMatter/claude-modsWrote 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.
[](https://agentmods.dev/skills/0xdarkmatter/claude-mods/leveldb-ops)<a href="https://agentmods.dev/skills/0xdarkmatter/claude-mods/leveldb-ops"><img src="https://agentmods.dev/badge/skills/0xdarkmatter/claude-mods/leveldb-ops/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/0xdarkmatter/claude-mods/leveldb-ops"><img src="https://agentmods.dev/badge/skills/0xdarkmatter/claude-mods/leveldb-ops.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to high
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- high Tool Misuse · line 44 Tool parameters are crafted to achieve unintended or unsafe behavior. Parameter abuse can bypass intended safety checks (e.g. shell=True, --force, dangerous glob patterns).Fix: Validate all tool parameters against an allowlist. Reject dangerous parameter values (shell=True, --force, -rf /) and use safe defaults.
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00070 | $0.01755 |
| Opus 5 | $0.00035 | $0.00877 |
| Sonnet 5 | $0.00014 | $0.00351 |
| Haiku 4.5 | $0.00007 | $0.00176 |
Grade A, and why
leveldb-ops 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 9d ago.
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.
How it starts
The opening of the file, as written. The whole thing — 152 lines — stays where its author put it; the contents beside it link to each section on GitHub.
LevelDB Operations
Read and decode LevelDB stores — primarily the Chromium/Electron storage layers (Local Storage, IndexedDB, Session Storage) used by every Electron app on disk: Claude Desktop, VS Code, Discord, Slack, Obsidian.
What is LevelDB
Embedded key-value store by Google. Sorted KV map, no SQL, no server. Format: a folder of .ldb (sorted runs), .log (write-ahead), MANIFEST-*, CURRENT, LOCK. Both keys and values are arbitrary bytes.
Chromium layers richer formats on top:
- Local Storage — flat key→string map, scoped per origin. Easiest to read.
- Session Storage — same shape, per-tab.
- IndexedDB — per-origin databases with object stores, indexes, versioned schemas. Encoded with v8 serialization. Needs a real reader.
When This Skill Triggers
- "What's in the Local Storage of "
- "Decode IndexedDB" / "read .ldb files"
- "Why does the sidebar show X" / "where does the desktop app cache Y"
- "Reset / mutate Electron app state"
- Forensic-style probes of Chrome/Edge/Brave/Electron state
Critical Safety Protocol
LevelDB uses an exclusive LOCK file. A running app holds it. Trying to open a live store fails OR silently returns stale snapshots.
Always copy before reading:
# Copy the entire leveldb dir to a temp location
cp -r "$APPDATA/Claude/Local Storage/leveldb" /tmp/probe/local-storage-db
cp -r "$APPDATA/Claude/IndexedDB/https_claude.ai_0.indexeddb.leveldb" /tmp/probe/indexeddb
# Remove the copied LOCK file so the reader can open it
rm -f /tmp/probe/local-storage-db/LOCK /tmp/probe/indexeddb/LOCK
The cp -r will warn Device or resource busy for the LOCK file itself — that's fine, the data files copy successfully.
Never write to the live store while the app is running. It will corrupt the LSM and crash the app. Quit the app first if you need to mutate.
Setup
plyvel and similar require native compilation and lack Windows wheels. Use ccl_chromium_reader — pure Python, written for browser forensics.
What ships with it
6 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 9d ago First seen · 152 lines · 70 tokens per session scan A 94dd890f02cf
leveldb-ops is a skill published in the GitHub repository 0xDarkMatter/claude-mods (34 stars, last pushed 17d ago), licensed MIT. It adds 70 tokens to every session and 1,755 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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