polar-billing SKILL.md skillA
polar-billing from fcakyon/claude-codex-settings is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add fcakyon/claude-codex-settings/polar-billing@git:20260827.a28ba93Pins git:20260827.a28ba93 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- fcakyon/claude-codex-settings
- Path
plugins/polar-skills/skills/polar-billing/SKILL.md- Versions recorded
- 3
- Latest version
- git:20260827.a28ba93, committed Aug 27, 2026
- First version recorded
- Apr 1, 2026
- Size
- 23,958 bytes
- Repository stars
- 1,200
- License
- Apache-2.0
This skill should be used when working on Polar billing system, Stripe integration, subscription lifecycle, checkout flows, or benefit provisioning.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Polar Billing System
Comprehensive guide to Polar's billing infrastructure, covering entities, flows, Stripe integration, and benefit provisioning.
## Quick Reference
```
Checkout → Payment → Order → Transaction → Benefits
↓
Subscription (if recurring)
↓
Subscription Cycle → Order → ...
```
## Table of Contents
1. [Core Entities](#1-core-entities)
2. [Entity Relationships](#2-entity-relationships)
3. [Main Services](#3-main-services)
4. [Dramatiq Background Tasks](#4-dramatiq-background-tasks)
5. [Stripe Integration](#5-stripe-integration)
6. [Subscription Lifecycle](#6-subscription-lifecycle)
7. [Proration System](#7-proration-system)
8. [Benefits & Credits](#8-benefits--credits)
9. [Dunning & Payment Retry](#9-dunning--payment-retry)
10. [Transaction Ledger](#10-transaction-ledger)
11. [Key File Locations](#11-key-file-locations)
---
## 1. Core Entities
### Checkout
**File:** `server/polar/models/checkout.py`
Shopping cart/payment session before order confirmation.
| Field | Type | Description |
|-------|------|-------------|
…Read the whole file at its exact version.
How to install
mdr add fcakyon/claude-codex-settings/polar-billing@sha256:29e8b87d2468951aThe line at the top of this page pins the label git:20260827.a28ba93, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_ueqm2gybqz42yh6m)
5 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 3 versions of this file, between Apr 1, 2026 and Aug 27, 2026, about one every 74 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20260827.a28ba93 latest | 2026-08-27 | a28ba93 | 23,958 B | A | view · diff |
| git:20260720.d26d2c8 | 2026-07-20 | d26d2c8 | 23,918 B | A | view · diff |
| git:20260401.d9d04a9 | 2026-04-01 | d9d04a9 | 21,414 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (23958 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
fcakyon/claude-codex-settings · 1,200 stars · license Apache-2.0 · pushed 2026-11-08 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_ueqm2gybqz42yh6m GET https://markdownregistry.com/api/v1/resolve?ref=fcakyon/claude-codex-settings/polar-billing GET https://markdownregistry.com/api/v1/blob/29e8b87d2468951a1fc982a9c2d168b02d481d65446ee48aceeba2dee1ca17bd
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.