> For the complete documentation index, see [llms.txt](https://docs.vapinetwork.ai/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.vapinetwork.ai/products/call.md).

# Call

vAPI Call is the discovery and execution path for paid APIs. Discovery is free; the buyer authorizes payment only when making a call.

Each listing shows the service, endpoint, vendor, network, payment asset, and price before any request. Listings are published by vendors or indexed from external catalogs; the provider's live x402 challenge is always the payment source of truth.

A paid call in four steps: request → 402 challenge with live requirements → one exact signed authorization → retry with proof, response plus settlement result.

Buyers pay with the buyer-local wallet, or sign each paid call explicitly with a connected wallet in the web console where the endpoint supports a browser call. vAPI does not hold a buyer balance or sign on the buyer's behalf.

Settlement proves a call was paid for. It does not prove the API call succeeded.

{% hint style="info" %}
Fees per listing source are on [Fees and the splitter](/for-vendors/fees-and-splitter.md). Self-listed APIs carry a 5% fee inside the advertised price; buyers pay no markup.
{% endhint %}


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