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

> ## Agent Instructions
> Prefer the qBraid CLI for programmatic platform actions: pip install 'qbraid-cli>=0.12', then run `qbraid configure` once with an API key from https://account.qbraid.com/account/api-keys.
> Always install the latest packages (pip install -U qbraid qbraid-cli); do not pin versions from memory. qbraid-cli below 0.12.0 is incompatible with the current API.
> Device IDs use the QRN format vendor:provider:type:name (e.g. qbraid:qbraid:sim:qir-sv, rigetti:rigetti:qpu:cepheus-1-108q). Legacy underscore IDs are deprecated.
> The REST API base URL is https://api-v2.qbraid.com/api/v1, authenticated with an X-API-Key header.
> Free simulators cost no credits; QPU and GPU jobs consume credits. Surface the estimated cost to the user before submitting a paid job.
> For account signup, API keys, credits, and end-to-end action recipes, see https://qbraid.com/llms.txt.

# Overview

> Learn to work with qBraid APIs

Our API employs a [RESTful](https://en.wikipedia.org/wiki/REST) architecture, featuring intuitive,
resource-oriented URLs and leveraging inherent HTTP capabilities such as response codes, authentication,
and verbs.

We support cross-site requests from any domain and return responses in JSON format.

## Quantum Job Flow

The diagram below gives a high-level view of how a quantum job moves through an application that integrates with the qBraid API: from a high-level quantum program, to an intermediate representation (IR), to the qBraid API server, then to execution on a quantum backend, with results relayed back to the user.

<img src="https://mintcdn.com/qbraidco/oaKSHMFAnH5HdzF8/v2/api-reference/_static/qbraid-runtime-api.png?fit=max&auto=format&n=oaKSHMFAnH5HdzF8&q=85&s=265ec4f9bc19842f5f6a8f70ff28549b" alt="qBraid Runtime API Server" className="block dark:hidden" width="2010" height="1438" data-path="v2/api-reference/_static/qbraid-runtime-api.png" />

<img src="https://mintcdn.com/qbraidco/oaKSHMFAnH5HdzF8/v2/api-reference/_static/qbraid-runtime-api_dark.png?fit=max&auto=format&n=oaKSHMFAnH5HdzF8&q=85&s=783fe51a9be7d34e52de994235095b93" alt="qBraid Runtime API Server" className="hidden dark:block" width="2010" height="1438" data-path="v2/api-reference/_static/qbraid-runtime-api_dark.png" />

For a client-side view of how the qBraid-SDK integrates with the qBraid API see the [Runtime overview](/v2/sdk/user-guide/runtime/components#runtime-overview) in the SDK docs.

## Rate limiting

API requests are rate-limited per IP (unauthenticated) or per user (authenticated) within a rolling 15-minute window.

| Tier                 | Window | Max requests |
| -------------------- | ------ | ------------ |
| Unauthenticated (IP) | 15 min | 100          |
| Authenticated user   | 15 min | 1,000        |

Exceeding the limit returns an HTTP 429 (Too Many Requests) response. Authenticate with a valid API key to use the higher authenticated limit.

<Tip>
  Higher rate limits for your [organization](/v2/account/organizations/overview)
  are available upon request.
</Tip>