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

# Welcome

Everything you need to use Capital AI from the app, your own code, or your terminal.

## Welcome to Capital AI

Capital AI is a market for GPU compute. You hold **contracts**, each one GPU for one calendar month, buy and sell them on the Capital AI exchange like any other instrument, and **deploy** the ones you keep: pair a provider's contract with the matching GPU contract, and the machines are provisioned for you for the month.

* **Find your way around.** Home, Markets, Compute and Offtake, and what each screen shows. Start [here](https://docs.capital.ai/app.md).
* **Open and fund an account.** Sign up, verify who you are, deposit by ACH, wire or stablecoin. Start [here](https://docs.capital.ai/about.md).
* **Buy compute.** Take a provider's listing on [Offtake](https://docs.capital.ai/app/offtake.md), or buy a benchmark contract on the [markets](https://docs.capital.ai/app/trade.md).
* **Deploy it.** Turn contracts into running GPUs on the [Compute](https://docs.capital.ai/app/compute.md) page.
* **Do it from code.** Create an API key and place your first order in five minutes. Start [here](https://docs.capital.ai/getting-started.md).
* **How a transaction works.** From sign-up to a running GPU, what moves where and what is recorded. [Transaction flow](https://docs.capital.ai/compute/transaction-flow.md).

![The Capital AI Home screen](https://mintcdn.com/capital-ai/2r_nz6EQ_1nQxtlD/images/home.jpg?fit=max\&auto=format\&n=2r_nz6EQ_1nQxtlD\&q=85\&s=9747fa80b01be3257f719b045b321ede)

## Basics

* **App:** [https://capital.ai](https://capital.ai)
* **API base URL:** `https://capital.ai`, the same host as the app. Every endpoint below is under `/api`.
* **Format:** JSON request and response bodies. Integers from the exchange (prices, quantities, timestamps) arrive as strings.
* **Authentication:** an API key in the `Authorization` header. See [Authentication](https://docs.capital.ai/authentication.md).
* **Errors:** standard HTTP status codes with a JSON body. See [Errors](https://docs.capital.ai/errors.md).


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