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 monte-carlo-data/mc-agent-toolkit --skill storage-cost-analysisgit clone --depth 1 https://github.com/monte-carlo-data/mc-agent-toolkitWrote 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/monte-carlo-data/mc-agent-toolkit/storage-cost-analysis)<a href="https://agentmods.dev/skills/monte-carlo-data/mc-agent-toolkit/storage-cost-analysis"><img src="https://agentmods.dev/badge/skills/monte-carlo-data/mc-agent-toolkit/storage-cost-analysis.svg" alt="Measured on agentmods" 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 Prompt Injection · line 78 Hidden instructions were detected in comments or invisible text. These could contain malicious directives. Manual review is recommended.Fix: Audit all comments and invisible characters. Remove any instructions that direct the agent to perform unauthorized actions. Use plain, reviewable content.
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 | $0.00051 | $0.01947 |
| Opus 5 | $0.00026 | $0.00974 |
| Sonnet 5 | $0.00010 | $0.00389 |
| Haiku 4.5 | $0.00005 | $0.00195 |
Grade A, and why
monte-carlo-storage-cost-analysis 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 8d 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.
Monte Carlo Storage Cost Analysis Skill
This skill analyzes a data warehouse for stale tables that can be removed to reduce storage costs. It delegates classification, safety scoring, and formatting to the analyze_storage_costs MCP tool, then presents the pre-formatted result verbatim and handles follow-up questions (category drill-downs, lineage checks).
Monte Carlo tool routing (required): Always call Monte Carlo MCP tools through this plugin's bundled server, whose fully-qualified tool names are
mcp__plugin_mc-agent-toolkit_monte-carlo-mcp__<tool>(e.g.mcp__plugin_mc-agent-toolkit_monte-carlo-mcp__get_alerts). Bare tool names used in this skill (get_alerts,search,get_table, …) refer to that bundled server. If the session also has a separately-configuredmonte-carlo-mcpserver, do not route to it — it may point at a different endpoint or credentials.
Reference file (use the Read tool to access it):
- Output contract and category keywords:
references/output-structure.md
When to activate this skill
Activate when the user:
- Asks about storage costs, waste, or cleanup opportunities
- Wants to find unused, unread, or stale tables
- Asks "which tables can I drop?" or "what's costing us money?"
- Mentions storage optimization, cost reduction, or warehouse cleanup
- Wants to identify zombie tables, dead-end pipelines, or temporary/archive tables
When NOT to activate this skill
Do not activate when the user is:
- Just querying data or exploring table contents
- Creating or modifying monitors (use the monitoring-advisor skill)
- Investigating data quality incidents (use the prevent skill)
- Looking at pipeline performance or query cost (use the performance-diagnosis skill)
Prerequisites
The following MCP tools must be available (connect to Monte Carlo's MCP server):
analyze_storage_costs-- runs the full analysis pipeline and returns pre-formatted outputget_asset_lineage-- used only for follow-up lineage checks
What ships with it
2 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.
- 8d ago First seen · 152 lines · 51 tokens per session scan A f7e7b4be643e
monte-carlo-storage-cost-analysis is a skill published in the GitHub repository monte-carlo-data/mc-agent-toolkit (91 stars, last pushed 14d ago), licensed Apache-2.0. It adds 51 tokens to every session and 1,947 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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