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Google Quantum AI website screenshot

Google Quantum AI

Google Quantum AI is Google's quantum-computing research and engineering arm, building superconducting quantum processors (most recently the Willow chip with below-threshold quantum error correction) and the open software stack that runs on them. The team operates the Quantum Computing Service via the Quantum Engine API (quantum.googleapis.com, v1alpha1), accessed primarily through the cirq-google Python client. Google Quantum AI also stewards a portfolio of Apache 2.0 open-source quantum software — Cirq, qsim, OpenFermion, Stim, Qualtran, TensorFlow Quantum, ReCirq, Tesseract, and Unitary — published under the quantumlib GitHub organisation, plus the Willow Early Access Program for sponsored researcher access to current hardware.

agent ready

Solid contracts, transparent operations, and an easy start — typically complete on four or five facets with one clear soft spot.

Kin Score

API Evangelist profiles Google Quantum AI the way a machine reads it — 48 machine-readable artifacts across 15 APIs, pulled from the provider's own public surface and indexed so a developer, an analyst, or an AI agent can evaluate it against every other provider on the network.

Every provider in the network is reduced to the same set of machine-readable artifacts — OpenAPI contracts, event specifications, GraphQL schemas, runnable collections, pricing and rate-limit signals, security posture, OAuth scopes, and the agent surfaces (MCP servers and skills) that let software drive the API on its own. We profile them because the interface is the part of a company you can actually inspect: it is a truer signal of what a provider does than any marketing page. From those artifacts we compute the Kin Score — Google Quantum AI scores 63.5/100 (strong), with a separate agent-readiness read of 55/100 (agent ready). The full breakdown is below, followed by every artifact we hold — each card links through to its machine-readable definition on apis.io.

Kin Score

This is the API Evangelist rating — a single, repeatable read computed from the artifacts on this page. Green fill is points earned; the red track is points possible, so every bar shows earned-versus-possible at a glance.

Kin Score Kin Score How this is scored →
scored 2026-07-27 · rubric v0.5
Composite quality — 63.5/100 · strong
Contract Quality 17.7 / 25
Developer Ergonomics 11.3 / 20
Commercial Clarity 12.1 / 20
Operational Transparency 4.8 / 13
Governance 8.8 / 12
Discoverability 8.8 / 10
Agent readiness — 55/100 · agent ready
Machine-Readable Contract 18 / 18
Agentic Access Contract 15 / 15
MCP Server 0 / 12
Machine-Readable Auth 10 / 10
Idempotency 0 / 9
Stable Error Semantics 0 / 8
Request/Response Examples 7 / 7
Rate-Limit Signaling 7 / 7
Typed Event Surface 0 / 6
Agent Skills 0 / 5
Well-Known Catalog 0 / 4
Consent & Bot Identity 0 / 3

How we profile Google Quantum AI

Each block below is one kind of artifact we hold for Google Quantum AI. For each we say what it is and why it earns a place in the profile, then list every one we've indexed — capped at two rows, scroll within the panel for the rest.

APIs 15

Each API is captured as its own OpenAPI definition — every operation, parameter, and response. This is the single most useful machine-readable description of what an API does, and it's what lets us score, lint, mock, and generate against it without asking the provider for anything.

Individual APIs this provider publishes, each with its own machine-readable definition.

Cirq

Cirq is an Apache 2.0 Python framework for designing, manipulating, simulating, and executing Noisy Intermediate-Scale Quantum (NISQ) circuits. Cirq is the canonical client libr...

qsim

qsim is a high-performance C++ state-vector simulator with a Python (qsimcirq) binding that plugs directly into Cirq. It is optimised for AVX/AVX-512, CUDA, and cuQuantum backen...

OpenFermion

OpenFermion is an Apache 2.0 library for translating quantum chemistry and materials science problems (electronic structure, fermionic operators, second quantisation) into quant...

Stim

Stim is a fast stabilizer-circuit simulator and detector-error-model toolchain that underpins Google Quantum AI's quantum error-correction work, including the Willow surface-cod...

Qualtran

Qualtran provides abstractions (Bloqs) for expressing, decomposing, and resource-estimating fault-tolerant quantum algorithms. It is Google Quantum AI's framework for reasoning ...

TensorFlow Quantum

TensorFlow Quantum (TFQ) is a hybrid quantum-classical machine learning library that integrates Cirq circuits as differentiable layers inside TensorFlow/Keras pipelines. Maintai...

ReCirq

ReCirq is a research-grade collection of reproducible Cirq experiments and applications published by Google Quantum AI, covering Fermi-Hubbard simulations, quantum chemistry ben...

Tesseract Decoder

Tesseract is a search-based maximum-likelihood decoder for quantum error correction that accompanies Stim. It targets surface-code and color-code decoding workloads used in Will...

Unitary

Unitary is an API library for adding quantum behaviours (superposition, entanglement, measurement) into classical games and interactive software, used in Google Quantum AI's edu...

Google Quantum AI Calibrations API

Periodic device performance snapshots.

Google Quantum AI Jobs API

Executions of a program against a processor or simulator backend.

Google Quantum AI Processors API

Quantum processing units (Willow, Sycamore-class) available to the project.

Google Quantum AI Programs API

Hardware-compatible circuits uploaded to a Google Cloud project.

Google Quantum AI Reservations API

Processor time-slot reservations and budgets.

Google Quantum AI Results API

Measurement results returned by completed jobs.

Scroll within the panel for all 15 ·

Open Collections 1

Open, tool-agnostic collections carry the same runnable value as Postman without locking you to one client — the portable, forkable form of the same exercise.

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

Google Quantum Engine API

OPEN COLLECTION

Pricing Plans 1

Pricing is part of the interface. Machine-readable plans tell you what a tier costs and includes before you commit — one of the six things the Kin Score reads for commercial clarity.

Published pricing tiers and plan structures.

Rate Limits 1

Rate limits are the difference between a demo that works and a production integration that doesn't fall over. Publishing them is an operational-transparency signal — and a hard requirement for any agent that plans its own throughput.

Documented rate limits and quota policies.

Google Quantum Ai Rate Limits

0 limits

RATE LIMITS

FinOps 1

Cost, billing, and metering signals let a buyer model the financial operations of an API before it's live. We profile them for the same reason we profile pricing: the money is part of the contract.

Cost, billing, and metering signals for API financial operations.

Features 17

The notable capabilities this provider advertises, captured as structured features so they can be searched and compared instead of read one landing page at a time.

Notable capabilities this provider offers.

Willow superconducting quantum processor with below-threshold quantum error correction
Quantum Engine REST/gRPC API (quantum.googleapis.com, v1alpha1) for program, job, processor, reservation, and calibration management
cirq-google as the canonical client (QuantumEngineServiceClient) wrapping the gRPC service
Cirq Python framework v1.6.x for NISQ circuit design, simulation, and execution
qsim high-performance state-vector simulator with CUDA + cuQuantum acceleration
OpenFermion for quantum chemistry and materials simulation
Stim stabilizer simulator and Tesseract decoder for surface-code QEC
Qualtran for fault-tolerant algorithm authoring and resource estimation
TensorFlow Quantum for hybrid quantum-classical machine learning
ReCirq library of reproducible research experiments
Willow Early Access Program for sponsored researcher access to the latest hardware
Google Cloud IAM / Application Default Credentials for authentication
Cirq integrations for AQT, IonQ, Pasqal, and Rigetti via dedicated subpackages
Quantum Virtual Machine (QVM) including the willow_pink target for noise-aware local simulation
Coursera "Quantum Error Correction" course produced with Google Quantum AI
Unitary game-development library for educational quantum applications
All Google Quantum AI open-source software is Apache 2.0 licensed

Scroll within the panel for all 17 ·

Semantic Vocabularies 1

JSON-LD contexts give the data shared meaning across APIs. We profile them because semantics are what let a machine reconcile 'customer' here with 'customer' somewhere else.

JSON-LD contexts and semantic vocabularies used across these APIs.

Google Quantum Ai Context

27 classes · 5 properties

JSON-LD

Spectral Rules 2

Governance rulesets we run against this provider's specs — the automated checks behind parts of the score. Profiling them makes the quality bar explicit and re-runnable, not a matter of opinion.

Google Quantum AI API Rules

5 rules · 3 warnings

SPECTRAL

Google Quantum AI API Rules

9 rules · 4 errors · 4 warnings

SPECTRAL

JSON Schema 2

Standalone JSON Schema definitions describe the data models behind the API. We profile them so the shapes are validatable on their own — useful long after a single request is forgotten.

Standalone JSON Schema definitions for this provider's data models.

QuantumJob

9 properties

JSON SCHEMA

QuantumProgram

7 properties

JSON SCHEMA

Examples 3

Real request and response payloads are what turn a spec from abstract into obvious — and they're one of the twelve things an agent needs to call an API correctly on the first try.

Example request and response payloads for these APIs.

Security Posture 2

Authentication, domain security, vulnerability disclosure, and trust-center signals — the evidence that a provider takes security seriously enough to document it. We profile it because you can't govern what you can't see.

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Google Quantum Ai Authentication

oauth2 · 1 scheme

SECURITY

Google Quantum Ai Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Scopes 1

OAuth scopes are the vocabulary of least-privilege access. Profiling them shows exactly what an integration — or an agent acting on a user's behalf — is allowed to do.

OAuth scopes governing access to this provider's APIs.

Google Quantum Ai Scopes

1 scope · authorizationCode

1 scopes

SCOPES

Agentic Access 1

An x-agentic-access contract marks which operations are safe for an agent to run on its own and which need a human in the loop. It is the difference between an API an agent can use and one it can use safely.

Recommended x-agentic-access execution contracts for AI agents.

Google Quantum Ai Agentic Access

27 operations · 12 acting

27 operations · 12 acting

AGENTIC

Resources

Every other property we hold for Google Quantum AI — documentation, portals, status pages, policies, and corporate surface — grouped by the job it does, following the integrator's arc from getting started to running in production.

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

Access & Security 3

Authentication, authorization, and security posture

Company 2

The organization behind the API

← All providers · Data indexed from github.com/api-evangelist/google-quantum-ai · machine-readable index on apis.io