Quantum API Godot Addon

Godot 4.x
Godot 4 runtime addon. Use the runtime client for health checks, text, gates, backend discovery, transpilation, and IBM circuit jobs. A Project Settings helper is optional.
Downloads, source, and demos
Godot Asset Library Legacy Godot asset library listing.Godot Asset Store Beta Godot asset store listing.Addon source Complete Godot addon source, including the optional settings helper.Demo project Quantum Jam Godot project using Quantum API gameplay calls.
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What this addon is

The Godot addon is a reusable runtime client with an optional editor helper for Project Settings. Add it to a game when you need health checks, text transforms, gate calls, backend discovery, transpile, or IBM circuit jobs from Godot code.

Install

Get the full addon from the Godot Asset Store or the Asset Library.
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Install the entire addons/quantum_api_client folder. The runtime script alone omits the optional settings helper.
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In Project → Project Settings → Plugins, enable Quantum API Client Settings to expose the fields under General → Quantum Api. You can also edit project.godot directly.
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Preload res://addons/quantum_api_client/quantum_api_client.gd from your game script.
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Create the client as a child node at runtime, then call apply_project_settings().

Configure project settings

The addon already points to the hosted Quantum API. For a local Health Check, select direct mode; no API address needs to be entered.
[quantum_api] backend_proxy_mode=false direct_api_key="" default_ibm_profile="" request_timeout_seconds=10.0
This starts with the hosted API for a local Health Check. A protected call needs a developer key supplied at runtime. For a shipped game, switch to backend proxy mode and set base_url to your own server, which keeps the upstream key private.

First call: Health Check

const QuantumApiClientScript = preload("res://addons/quantum_api_client/quantum_api_client.gd") var quantum_api_client: QuantumApiClient func _ready() -> void: quantum_api_client = QuantumApiClientScript.new() add_child(quantum_api_client) quantum_api_client.apply_project_settings() quantum_api_client.health_check(func(success: bool, payload: Dictionary) -> void: print(success, payload) )

Run Gate example

For this developer-only direct-mode call, read an existing key from the process environment. Keep direct_api_key empty in project files and exported games.
var developer_key := OS.get_environment("QUANTUM_API_KEY") if developer_key.is_empty(): push_error("QUANTUM_API_KEY is required for Run Gate") return quantum_api_client.set_api_key(developer_key) quantum_api_client.run_gate("rotation", func(success: bool, payload: Dictionary) -> void: print(success, payload) , PI / 2.0)

Backend proxy vs direct API key

Backend proxy mode
Keep this true for a shipped game. Your backend keeps the upstream API key out of the client.
Direct API key
For a developer-controlled local test. Read a short-lived key from the process environment; never save it in project.godot or an exported game.
Default IBM profile
An optional saved profile name used by IBM runtime calls when one is not supplied for that call.

IBM hardware jobs

Use an existing IBM profile name. Pass it for IBM calls or set default_ibm_profile in project settings.
IBM hardware jobs have to wait in a queue before starting; get started at quantum.cloud.ibm.com.
quantum_api_client.list_backends(func(success: bool, payload: Dictionary) -> void: print(success, payload) , "ibm")

Available calls

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health_check, transform_text, run_gate
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list_backends, transpile, submit_circuit_job
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get_circuit_job and get_circuit_job_result for polling a submitted hardware job

Troubleshooting

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Start with health_check to distinguish a connection problem from a request-shape problem.
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When using direct mode, create an API key through the Quantum API account page and keep it out of a distributed build.
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For IBM calls, verify the selected profile and backend availability before submitting a job.

Feedback, contributions, comments, and questions

Questions, corrections, and issue reports are welcome. Email MrDJ@DavidJGrimsley.com or open an issue at github.com/davidjgrimsley/quantum-api/issues.
Install the Quantum API skill
Add the agent skill when you want coding assistants to find the Quantum API guides and integration notes quickly.

Agent version (.md)

Coding agents can use the plain Markdown companion for this guide at /public-facing/api/quantum/godot-addon.md.