> ## Documentation Index
> Fetch the complete documentation index at: https://docs.useautumn.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Welcome to Autumn

> Drop-in, open-source control layer for AI and SaaS monetization.

## What is Autumn?

Autumn is your source of truth for billing and entitlements between your application and Stripe.

It manages subscription state, credit balances, feature entitlements, and usage enforcement — the logic you'd otherwise build and maintain across your codebase, database, and Stripe webhooks.

Your app can query Autumn inline to determine what a customer is allowed to do (send an AI message, access SSO, add a seat) and to track usage against their balance.

Because billing logic lives in Autumn, pricing changes and custom deals become a simple configuration change. No migrations or rebuild.

## Why use Autumn?

AI monetization is harder than what came before. For reference, OpenAI wrote a [post](https://openai.com/index/beyond-rate-limits/) about their in-house system.

| Area             | What you'd build                                                                                 |
| ---------------- | ------------------------------------------------------------------------------------------------ |
| Subscriptions    | Checkouts, proration, schedules, add-ons, trials.                                                |
| Credit ledgers   | Real-time enforcement, periodic and one-time grants, rollovers, expiration, concurrency control. |
| Observability    | Usage history charts, groups and filters, logs, ClickHouse.                                      |
| Entitlements     | Feature gating per plan, boolean and metered features, seat-based allowances.                    |
| Billing Controls | Spend caps, auto top-ups, overage handling, usage alerts.                                        |
| Pricing changes  | Versioning, grandfathering, migration scripts, backwards compatibility.                          |
| Enterprise       | Custom contracts, tiered pricing, per-customer credit grants, expansion logic.                   |
| Edge cases       | Plan switching, monthly↔annual changes, failed payments, 3DS, race conditions, refunds.          |

Billing starts with a simple checkout flow, and balloons in complexity as you add more features and scale. And when you want to change your pricing, you need to rebuild everything. Yet, it's a critical part of your product that you cannot afford to get wrong.

You can choose to build this yourself, or use Autumn to offload all this logic out of your codebase. It's less work, more flexible, and more reliable.

## How is this different?

Other billing tools are designed for post-hoc invoicing: you send usage events, they generate invoices at end of period. Your app still owns access control, usage limits, and plan change logic.

Autumn is a real-time system of record. You can query it for the current state of any customer (plan, entitlements, balances) inline, via cache, or via webhooks. Because Autumn owns the state (not your code or database), edge cases like proration, failed payments, and concurrency are handled automatically. Pricing changes become config, not code.

Autumn builds on top of Stripe rather than replacing it. Your subscriptions, customers, and payment details stay in your own Stripe account.

<Check>
  While Autumn's core focus is credit-based AI monetization, it handles any SaaS pricing model. Many of our users have no usage-based features at all, and just prefer the developer experience (eg, no webhooks).
</Check>

## FAQ

<AccordionGroup>
  <Accordion title="Do I still need Stripe?">
    Yes. Autumn works with Stripe — it handles the billing logic that Stripe doesn't. You keep your Stripe account, your customer relationships, and your payment data. Autumn sits between your app and Stripe, managing webhooks, usage limits, and state.

    Your subscriptions live in Stripe. You're never locked in.
  </Accordion>

  <Accordion title="Do I need to call Autumn before every action?">
    For latency-sensitive operations, you may not want to make an `autumn.check()` network call before every action.

    You can either cache the Autumn customer data on your end, or use the `customer.products.updated` webhook to replicate Autumn state into your own system.
  </Accordion>

  <Accordion title="What if Autumn goes down?">
    Not being able to reach Autumn does not mean your app goes down. The SDKs default to fail-open and fail-fast, meaning in a worst case, some users get temporary additional access.

    We can help reconcile usage tracking and balances afterward if needed.
  </Accordion>

  <Accordion title="How is Autumn different from Orb or Metronome?">
    Orb and Metronome focus on usage metering — tracking how much customers consume for end-of-period invoicing. You still build access control and state management separately.

    Autumn is a complete system of record: usage metering, entitlements, feature gating, and billing state in one API.
  </Accordion>

  <Accordion title="Am I locked in?">
    Autumn is open source. You can self-host anytime, or export all your data. Your Stripe subscriptions, customers, and payment details remain yours.

    You can migrate gradually: replicate customer state into your own system via webhooks, then make a full transition.
  </Accordion>

  <Accordion title="Can you do the implementation for us?">
    If you're setting up payments for the first time, most teams go live in under an hour. Migrating from an existing billing system typically takes 1–2 weeks depending on complexity.

    For larger companies, we provide a forward-deployed service: dual-write to your internal system and Autumn, then migrate over.
  </Accordion>

  <Accordion title="Can you handle our event volume?">
    Autumn supports 10,000+ events per second per end customer. If you have specific throughput requirements, reach out and we'll walk through the architecture.
  </Accordion>
</AccordionGroup>

<CardGroup cols={2}>
  <Card title="Reach out to us" icon="envelope" href="mailto:hey@useautumn.com">
    We'll help you model your pricing and go live in a couple of days.
  </Card>

  <Card title="Join us on Discord" icon="discord" href="https://discord.gg/STqxY92zuS">
    Connect with us, other users, and get integration support within minutes.
  </Card>
</CardGroup>