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 benjaminasterA/antigravity-awesome-skills --skill billing-automationgit clone --depth 1 https://github.com/benjaminasterA/antigravity-awesome-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/benjaminastera/antigravity-awesome-skills/billing-automation)<a href="https://agentmods.dev/skills/benjaminastera/antigravity-awesome-skills/billing-automation"><img src="https://agentmods.dev/badge/skills/benjaminastera/antigravity-awesome-skills/billing-automation/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/benjaminastera/antigravity-awesome-skills/billing-automation"><img src="https://agentmods.dev/badge/skills/benjaminastera/antigravity-awesome-skills/billing-automation.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 | $0.00039 | $0.00310 |
| Opus 5 | $0.00019 | $0.00155 |
| Sonnet 5 | $0.00008 | $0.00062 |
| Haiku 4.5 | $0.00004 | $0.00031 |
Grade A, and why
billing-automation 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 7d 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.
This is a copy
88% identical to billing-automation — 4 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
What it actually says
Billing Automation
Master automated billing systems including recurring billing, invoice generation, dunning management, proration, and tax calculation.
Use this skill when
- Implementing SaaS subscription billing
- Automating invoice generation and delivery
- Managing failed payment recovery (dunning)
- Calculating prorated charges for plan changes
- Handling sales tax, VAT, and GST
- Processing usage-based billing
- Managing billing cycles and renewals
Do not use this skill when
- You only need a one-off invoice or manual billing
- The task is unrelated to billing or subscriptions
- You cannot change pricing, plans, or billing flows
Instructions
- Define plans, pricing, billing intervals, and proration rules.
- Map subscription lifecycle states and renewal/cancellation behavior.
- Implement invoicing, payments, retries, and dunning workflows.
- Model taxes and compliance requirements per region.
- Validate with sandbox payments and reconcile ledger outputs.
- If detailed templates are required, open
resources/implementation-playbook.md.
Safety
- Do not charge real customers in testing environments.
- Verify tax handling and compliance obligations before production rollout.
Resources
resources/implementation-playbook.mdfor detailed patterns, checklists, and examples.
What ships with it
1 file 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.
- 7d ago First seen · 45 lines · 39 tokens per session scan A 08d64fa3e67c
billing-automation is a skill published in the GitHub repository benjaminasterA/antigravity-awesome-skills (264 stars, last pushed yesterday), licensed MIT. It adds 39 tokens to every session and 310 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 88% identical to billing-automation, differing in 4 lines, and is treated as a copy.
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