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 roedyrustam/vibes-plug --skill saas-billinggit clone --depth 1 https://github.com/roedyrustam/vibes-plugWrote 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/roedyrustam/vibes-plug/saas-billing)<a href="https://agentmods.dev/skills/roedyrustam/vibes-plug/saas-billing"><img src="https://agentmods.dev/badge/skills/roedyrustam/vibes-plug/saas-billing/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/roedyrustam/vibes-plug/saas-billing"><img src="https://agentmods.dev/badge/skills/roedyrustam/vibes-plug/saas-billing.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 | $0.00051 | $0.04525 |
| Opus 5.5 | $0.00020 | $0.01810 |
| Sonnet 5.5 | $0.00010 | $0.00905 |
| Haiku 4.5 | $0.00005 | $0.00453 |
Grade A, and why
saas-billing 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 3d 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 — 406 lines — stays where its author put it; the contents beside it link to each section on GitHub.
SaaS Billing Expert (2026 Edition)
English
Orchestration & Integration
- Payment Gateways & Providers:
payment-gateway-expert,doku-payment-gateway,agentic-m2m-settlement,agentic-micro-economy-architect - Database & Subscription State:
database-orm-expert,saas-multi-tenant,saas-architect - Security & Post-Quantum Crypto:
post-quantum-crypto-migrator,zero-trust-secret-vault,autonomous-red-teamer - Background Queues & Notifications:
async-queue-temporal-expert,email-notification-expert,sse-websocket-streaming-expert - Lifecycle & Governance:
production-ready-hardener,brainstorming,zero-to-prod-orchestrator,session-memory-manager
Description
Expert guide for implementing and auditing SaaS billing systems. Covers subscription state machines, secure webhook handling, atomic database synchronization, and the 2026 billing landscape including Stripe, Polar.sh (open-source, developer-first), LemonSqueezy, Paddle, DOKU (Checkout & SNAP BI), and Midtrans (for Southeast Asia).
Trigger Conditions
- Integrating any payment gateway (Stripe, Polar.sh, LemonSqueezy, DOKU Checkout / SNAP BI, Midtrans, PayPal) into a SaaS application.
- Using a Static-to-Dynamic QRIS alternative (with unique nominals and mutation webhooks) for local developers without PG accounts.
- Implementing subscription state machines (active → past_due → canceled → reactivated).
- Building secure webhook handlers with signature verification and atomic idempotency.
- Syncing external subscription status to a local database.
- Implementing usage-based billing or metered API pricing.
- Building the customer billing portal (manage subscription, download invoices).
- Auditing an existing billing system for security gaps.
2026 Billing Provider Landscape
| Provider | Best For | Open Source | Merchant of Record |
|---|---|---|---|
| Stripe | Enterprise, global, complex billing | ❌ | ❌ |
| Polar.sh | Developer-first, open-source products | ✅ | ✅ (optional) |
| LemonSqueezy | Indie hackers, simple pricing, global | ❌ | ✅ |
| Paddle | B2B SaaS, EU VAT compliance | ❌ | ✅ |
| DOKU (Checkout & SNAP BI) | Indonesia & SE Asia enterprise, QRIS, VA, Multi-channel | ❌ | ❌ |
| Midtrans | Southeast Asia / Indonesia | ❌ | ❌ |
| PayPal | Global, consumer trust | ❌ | ❌ |
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.
- 3d ago Changed · +8 lines b3763f834158
- 4d ago Changed · +1 lines e1c74f946f16
- 6d ago Changed · +2 lines 36ca830f73f6
- 7d ago Changed aa1c66fd6fdb
- 16d ago Changed 53bb02459a5b
- 21d ago Changed 198e49071ebf
- 22d ago Changed 8091df9f756c
- 1mo ago Changed · +11 lines 1bd07e1db246
- 1mo ago Changed 7d9c19a9a305
- 1mo ago First seen · 384 lines · 51 tokens per session scan A 2d146ef17060
saas-billing is a skill published in the GitHub repository roedyrustam/vibes-plug (113 stars, last pushed today), licensed MIT. It adds 51 tokens to every session and 4,525 once invoked, about $0.0002 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 2026-09-03.
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stripe-best-practices
Guides Stripe integration decisions across development and test environment planning (separate sandboxes vs the shared test mode sandbox), API selection (Checkout Sessions vs PaymentIntents), Connect platform setup (Accounts v2, controller properties), billing/subscriptions, tax and registrations (Stripe Tax…
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dunning-escalation
Per-subscription dunning ladder for recovering failed Stripe payments — smart retry, payment reminder, update-your-card notice, final notice — with minimum wait times between rungs, the ledger format that carries state across hourly runs, and the stop-for-human line at cancellation, credits, and refunds.
Braintree Automation
Braintree Automation: manage payment processing via Stripe-compatible tools for customers, subscriptions, payment methods, and transactions.