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 int2t05/engineering-skills --skill cost-optimizationgit clone --depth 1 https://github.com/int2t05/engineering-skillsWrote 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/int2t05/engineering-skills/cost-optimization)<a href="https://agentmods.dev/skills/int2t05/engineering-skills/cost-optimization"><img src="https://agentmods.dev/badge/skills/int2t05/engineering-skills/cost-optimization/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/int2t05/engineering-skills/cost-optimization"><img src="https://agentmods.dev/badge/skills/int2t05/engineering-skills/cost-optimization.svg" alt="Reviewed on agentmods" width="80" 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 5.1 | $0.00023 | $0.00294 |
| Opus 5.5 | $0.00009 | $0.00118 |
| Sonnet 5.5 | $0.00005 | $0.00059 |
| Haiku 4.5 | $0.00002 | $0.00029 |
Grade A, and why
cost-optimization 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.
What it actually says
Cost Optimization
When to use
- Reduce measured cost while preserving required service quality.
Not for: performance for latency; architecture for unbuilt systems.
Steps
-
Establish comparable billing, workload and service-quality baselines; redact account details.
-
Attribute dominant controllable costs across actual compute, storage, network, services and model calls.
-
Compare savings, effort, reliability and recovery; apply the smallest authorized change.
-
Re-measure under comparable conditions and label observed, estimated and unmeasurable savings.
Output: Suggested paths, subject to human audit: COST.md only for a useful continuing ledger.
Verify
- Cost comparisons state period and workload; quality regressions and estimated savings are explicit.
References
- engineering-principles.md — shared decision boundaries, scope and verification.
- human-audit.md — document consent, readability and human review.
- references/cost-drivers.md — symptom→cause map for cloud spend: over-provisioning, idle resources, egress, storage lifecycle, reserved-capacity gaps, with per-platform levers
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 Changed · -33 lines · +23 tokens per session 4d2efd581235
- 15d ago Changed · +2 lines 23b04c12f8f5
- 1mo ago First seen · 66 lines · 0 tokens per session scan A 5f556c243730
cost-optimization is a skill published in the GitHub repository int2t05/engineering-skills (3 stars, last pushed 9d ago), licensed MIT. It adds 23 tokens to every session and 294 once invoked, about $0.0001 per session on Opus 5.5. 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 2026-08-31.
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