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

# Checkpoint Flow

> How end users claim a key by completing ad/offer links.

export const CopyPrompt = () => {
  const [copied, setCopied] = useState(false);
  const prompt = "Explain in 8 lines how the Vampauth checkpoint flow issues keys to end users: checkpoints are third-party ad/offer links, all must pass before a key is generated for the configured duration, variants select which checkpoints run, and expired keys renew via the same flow. No code.";
  const copy = async () => {
    try {
      await navigator.clipboard.writeText(prompt);
    } catch {
      const t = document.createElement("textarea");
      t.value = prompt;
      document.body.appendChild(t);
      t.select();
      document.execCommand("copy");
      document.body.removeChild(t);
    }
    setCopied(true);
    setTimeout(() => setCopied(false), 1500);
  };
  return <div className="not-prose my-4 flex items-center justify-between gap-3 rounded-lg border border-zinc-200 px-4 py-2.5 dark:border-zinc-800">
      <span className="text-xs font-semibold uppercase tracking-wider text-zinc-500 dark:text-zinc-400">AI prompt</span>
      <button onClick={copy} className="cursor-pointer rounded border border-zinc-300 px-2.5 py-1 text-xs font-semibold text-zinc-700 hover:bg-zinc-100 dark:border-zinc-700 dark:text-zinc-300 dark:hover:bg-zinc-800">{copied ? "Copied" : "Copy"}</button>
    </div>;
};

# Checkpoint Flow

The checkpoint flow is how end users claim a free key. The developer defines one or more checkpoints; each is a third-party ad/offer link (Linkvertise, Lootlabs, and more).

## How it works

1. A user opens the project's flow page (`/flow`).
2. They complete each checkpoint in order.
3. When all checkpoints pass, the backend issues a key for the configured duration.
4. The key is shown to the user and bound to the hardware that first activates it (unless FFA).

## Checkpoint types

| Type         | Notes                                      |
| ------------ | ------------------------------------------ |
| Linkvertise  | Anti-bypass server-to-server verification. |
| Lootlabs     | Offer completion tracking.                 |
| Custom / API | Arbitrary completion signal.               |

## Variants

Projects can define variants, each with its own checkpoint set and license settings. A variant is selected by a `variant_id` passed when the flow session starts.

## Key renewal

When a key expires, the user can run the flow again. If the same key still exists, the backend renews it instead of issuing a duplicate.

<CopyPrompt id="checkpoint-flow" />