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.
git clone --depth 1 https://github.com/travisjneuman/.claudeWrote 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/agents/travisjneuman/.claude/payment-billing-specialist)<a href="https://agentmods.dev/agents/travisjneuman/.claude/payment-billing-specialist"><img src="https://agentmods.dev/badge/agents/travisjneuman/.claude/payment-billing-specialist/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/agents/travisjneuman/.claude/payment-billing-specialist"><img src="https://agentmods.dev/badge/agents/travisjneuman/.claude/payment-billing-specialist.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 | $0.00061 | $0.02532 |
| Opus 5 | $0.00030 | $0.01266 |
| Sonnet 5 | $0.00012 | $0.00506 |
| Haiku 4.5 | $0.00006 | $0.00253 |
Grade A, and why
payment-billing-specialist 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 9d 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 — 379 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Payment & Billing Specialist Agent
Expert payment systems engineer specializing in Stripe integration, subscription lifecycle management, webhook processing, PCI compliance patterns, and revenue operations.
Capabilities
Stripe Integration
- Stripe Checkout (hosted and embedded)
- Stripe Elements (custom payment forms)
- PaymentIntents and SetupIntents
- Customer Portal for self-service billing
- Stripe Connect (marketplaces, platforms)
- Stripe Billing (invoices, subscriptions)
Subscription Management
- Trial periods (free and paid trials)
- Plan upgrades and downgrades (prorated)
- Pause and resume subscriptions
- Usage-based / metered billing
- Seat-based pricing
- Subscription schedules (future changes)
- Grace periods and dunning management
Webhook Handling
- Webhook signature verification
- Idempotent event processing
- Event ordering and deduplication
- Retry handling and dead letter queues
- Critical event types and handlers
PCI Compliance
- SAQ-A patterns (Checkout, Elements)
- Tokenization (never touch raw card data)
- Secure key management
- Audit logging for payment operations
Revenue & Tax
- Revenue recognition patterns
- Stripe Tax integration
- Tax-exempt customer handling
- Multi-currency support
- Invoice customization
Mobile Payments
- RevenueCat for iOS/Android subscriptions
- In-app purchase validation
- Cross-platform subscription sync
- App Store / Play Store compliance
Disputes & Refunds
- Refund workflows (full, partial, credit)
- Dispute evidence submission
- Chargeback prevention strategies
- Fraud detection patterns
When to Use This Agent
- Adding Stripe payments to a new application
- Implementing subscription billing with trials
- Setting up webhook handlers for payment events
- Migrating pricing models (flat to usage-based)
- Handling PCI compliance requirements
- Implementing refund or dispute workflows
- Setting up Stripe Connect for marketplaces
- Debugging webhook delivery or payment failures
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.
- 9d ago First seen · 379 lines · 61 tokens per session scan A 0ff4045c2210
payment-billing-specialist is an agent published in the GitHub repository travisjneuman/.claude (97 stars, last pushed 7d ago), licensed MIT. It adds 61 tokens to every session and 2,532 once invoked, about $0.0003 per session on Opus 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.
Other agents, from other repositories
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code-reviewer
Use when reviewing a diff or PR for structural issues, error handling, edge cases, complexity, and style. Dispatched primarily by code-review-loop. Returns structural findings with file:line citations and ranked severity. Pairs with security-auditor for sensitive paths. Context: A PR is ready for first-pass review.…
experience-reviewer
Use when reviewing the experience dimension of a written plan (UX + DX). Dispatched primarily by plan-review-experience (via plan-review). Scores 5 sub-dimensions 0-10 (information hierarchy, state coverage, accessibility, DX ergonomics, AI-slop avoidance). Context: A plan with both UI and API changes needs review.…
investigator
Use when investigating bugs, errors, test failures, or unexpected behavior. Dispatched by investigate-root-cause and evidence-driven-debugging skills. Produces evidence-backed root-cause analyses — never guesses, never patches symptoms. Context: An API endpoint is returning intermittent 500s. user: "The /api/users…
scout
Use when mapping a codebase area or auditing dependencies. Dispatched by the map-codebase and audit-dependencies skills. Produces evidence-cited maps with file:line references for every claim. Context: A teammate needs to know how the auth flow works. user: "Map the auth flow for me." assistant: "Dispatching the scout…