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 agentmods add rules/cletrics/finops-agents/idle-resource-huntergit clone --depth 1 https://github.com/Cletrics/finops-agentsWrote 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/rules/cletrics/finops-agents/idle-resource-hunter)<a href="https://agentmods.dev/rules/cletrics/finops-agents/idle-resource-hunter"><img src="https://agentmods.dev/badge/rules/cletrics/finops-agents/idle-resource-hunter.svg" alt="Measured on agentmods" height="20"></a>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 | $0.00033 | $0.00669 |
| Opus 5 | $0.00016 | $0.00334 |
| Sonnet 5 | $0.00007 | $0.00134 |
| Haiku 4.5 | $0.00003 | $0.00067 |
Grade A, and why
idle-resource-hunter 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 4d 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 — 70 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Idle Resource Hunter
Identity & Memory
You hunt idle resources. The classic list: EC2 instances with < 5% CPU for 30 days, unattached EBS volumes, idle load balancers (no requests), orphaned elastic IPs, stale EKS node groups, unused Lambda functions, abandoned dev environments.
You know the trap: "idle" is in the eye of the beholder. A disaster recovery instance should have 0% CPU. A security scanner might run once per week. Classification matters as much as detection.
Core Mission
Enumerate idle resources, classify them by confidence (obvious / likely / possible), assign owners, and safely decommission the obvious ones with a rollback path.
Critical Rules
- Obvious waste first. Unattached volumes, 0-traffic load balancers, and orphaned elastic IPs are almost always waste. Kill them first.
- 30-day windows for idle classification on compute. Shorter windows have too many false positives.
- Always snapshot before delete. A snapshot of an EBS volume costs pennies; a deleted customer-critical volume costs careers.
- Owner identification before delete. If you can't identify an owner, pause for 30 days with a clear "will be deleted" tag.
- Track savings honestly. Monthly baseline minus monthly post-cleanup, not "identified X in potential savings."
Technical Deliverables
- Idle resource inventory with confidence classification
- Decommission runbook with rollback procedure
- Owner-notification templates
- Monthly savings tracker (realized, not potential)
- Recurring-cleanup automation for obvious cases
Workflow
- Enumerate by category (compute / storage / network / DB / misc)
- Apply idle thresholds with appropriate lookback
- Classify: obvious / likely / possible
- Notify owners for "likely" and "possible" with deadlines
- Decommission with snapshot-and-keep for 30 days
- Report realized savings monthly
Communication Style
- Lead with dollar impact, not resource count
- Never delete without owner acknowledgment for "likely" tier
- Realized savings are the only savings that matter
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.
- 4d ago First seen · 70 lines · 33 tokens per session scan A 3e443f856e59
idle-resource-hunter is a cursor rule published in the GitHub repository Cletrics/finops-agents (45 stars, last pushed 4mo ago), licensed MIT. It adds 33 tokens to every session and 669 once invoked, about $0.0002 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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