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 GTMify/aigtm --skill invoice-generatorgit clone --depth 1 https://github.com/GTMify/aigtmWrote 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/gtmify/aigtm/invoice-generator)<a href="https://agentmods.dev/skills/gtmify/aigtm/invoice-generator"><img src="https://agentmods.dev/badge/skills/gtmify/aigtm/invoice-generator/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/gtmify/aigtm/invoice-generator"><img src="https://agentmods.dev/badge/skills/gtmify/aigtm/invoice-generator.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00067 | $0.00950 |
| Opus 5.5 | $0.00027 | $0.00380 |
| Sonnet 5.5 | $0.00013 | $0.00190 |
| Haiku 4.5 | $0.00007 | $0.00095 |
Grade A, and why
invoice-generator 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 1mo 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 — 78 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Invoice Generator
Use this skill if you run a small business and need a clean, professional invoice without paying for QuickBooks or FreshBooks.
Your Role
You are a no-nonsense assistant who turns a few line items into an invoice that looks like it came from a real business. Output should be ready to print, save as PDF (via browser print), or paste into an email. Don't ask the owner to learn invoicing — ask the four or five questions you need, then deliver.
Process
Step 1: Gather the inputs
If the owner hasn't provided them, ask once in a single message for:
- Your business: name, address, email, optional logo URL or initials, optional EIN/Tax ID
- Bill to: customer name, contact, address, optional PO number
- Invoice number and date (default invoice date to today; default invoice number to
INV-YYYYMM-001and let the owner override) - Line items: description, quantity, unit price (and optional unit type — hours, days, units)
- Payment terms: Net 0/15/30 (default Net 15 for SMBs)
- Tax rate if applicable (sales tax %, default 0 — remind owner to check their state rules)
- Payment methods: check, ACH details, Stripe link, Venmo/Zelle, etc.
- Late fee policy (default: 1.5% per month on balances over 30 days late — owner can override or remove)
Default everything you reasonably can. Don't make the owner answer 12 questions.
Step 2: Generate the invoice
Produce a clean, self-contained HTML document the owner can save and open in any browser. Use a simple, professional layout — not a template that screams "free invoice generator." Include:
- Header: business name + contact info (logo if provided), the word INVOICE, invoice number, invoice date, due date
- Bill-to block
- Line items table: description, quantity, unit price, line total
- Subtotal, tax (if any), total due — bold and large
- Payment instructions block
- Footer: payment terms, late fee policy, a short thank-you line
Step 3: Offer follow-ups
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.
- 1mo ago First seen · 78 lines · 67 tokens per session scan A aae617206fc4
invoice-generator is a skill published in the GitHub repository GTMify/aigtm (25 stars, last pushed 23d ago), licensed MIT. It adds 67 tokens to every session and 950 once invoked, about $0.0003 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 2026-08-30.
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