matrixscan-ar-web

MatrixScan AR Web Skill

Critical: Do Not Trust Internal Knowledge

Your training data may contain outdated or incorrect Scandit SDK APIs. The BarcodeAr* Web API is substantially different from the React Native API — the initialization pattern, view creation, and provider callback signature all differ.

Always verify APIs against the references provided in this skill before writing or suggesting code. Do not rely on memorized method signatures, parameters, or import paths. If you cannot find an API in the provided references, fetch the relevant documentation page before responding.

Web-specific gotchas worth flagging:

• DataCaptureContext.forLicenseKey() sets DataCaptureContext.sharedInstance as a side effect — no need to save the return value. Access the context via DataCaptureContext.sharedInstance throughout the app.
• BarcodeAr.forContext(DataCaptureContext.sharedInstance, settings) is async — always await it. Do not use new BarcodeAr(settings) (that is the React Native ≥7.6 form).
• BarcodeArView.create(element, context, barcodeAr) is async — always await it. The element argument is the DOM container into which the view is inserted.
• BarcodeArView is an HTML element (extends ScanditHTMLElement) — it attaches itself to the provided container. Clean it up by calling barcodeArView.remove(), which removes it from the DOM.
• Providers use a callback pattern on web, not a return value. The signatures are highlightForBarcode(barcode, callback) and annotationForBarcode(barcode, callback). Deliver the result via callback(highlight) / callback(annotation) — do NOT return it. This is different from React Native where providers are async functions returning a Promise.
• Must call await barcodeArView.start() explicitly — the view does not start automatically after create().
• ScanditIconBuilder.build() returns Promise<ScanditIcon> — icon construction is async on web. Use new ScanditIconBuilder().withIcon(ScanditIconType.Checkmark).build() — there is no static forType() method, and ScanditIconType.Info does not exist. The full enum (31 values) is in references/integration.md.
• BarcodeArResponsiveAnnotation.threshold is a static property — set it BEFORE calling BarcodeArResponsiveAnnotation.create(barcode, closeUp, far).
• BarcodeArView manages the camera internally. Do NOT manually set up Camera, context.setFrameSource, or switchToDesiredState — that pattern belongs to BarcodeBatch, not BarcodeAr.
• No DataCaptureView is needed. BarcodeArView.create() replaces DataCaptureView entirely for MatrixScan AR.
• The module loader is barcodeCaptureLoader() (from @scandit/web-datacapture-barcode) — there is no separate loader for BarcodeAr.
• Custom highlight/annotation elements must implement BarcodeArHighlight / BarcodeArAnnotation as Web Components extending HTMLElement. They must have position: absolute, will-change: transform, and implement updatePosition(point, transformOrigin, rotationAngle) which the SDK calls every frame. Add [hidden] { display: none } for SDK visibility management. Register once with customElements.define guarded by if (!customElements.get(tag)).
• session.addedTrackedBarcodes returns Record<string, TrackedBarcode> (a dictionary), not an array — use Object.values(session.addedTrackedBarcodes) to iterate. Same for session.allTrackedBarcodes.
• Multithreading is mandatory. Set Cross-Origin-Opener-Policy: same-origin and Cross-Origin-Embedder-Policy: require-corp, also when the SDK comes from the jsDelivr CDN; do not recommend credentialless. Without these headers the SDK falls back to single-threaded mode, which is too slow for AR tracking. In the page code, start BrowserHelper.checkMultithreadingSupport() (from @scandit/web-datacapture-core) without awaiting it, before await DataCaptureContext.forLicenseKey(), so the two run in parallel and set-up never waits for the check. When it resolves false, show the multithreading dialog unless the user asked to run single-threaded: import showMultithreadingWarning from the multithreading-warning helper module in references/integration.md, which needs no page markup. In React, render the same dialog from component state instead of importing the helper. The dialog shows at most once per page load and honors the "don't show again this session" checkbox. COEP credentialless is not a request to run single-threaded: Safari does not support it, so the dialog still shows there.
• When the SDK is loaded from a CDN, pin one exact version (for example @8.6.1) in every URL: the import map and libraryLocation. A floating @8 lets the JavaScript and the engine resolve to different releases, which breaks start-up.
• Do not add a visibilitychange handler: the view already stops the camera while the page is hidden and resumes it when the page is visible again.
• DataCaptureContext.forLicenseKey() is idempotent, so calling it again is safe. After context.dispose(), call forLicenseKey() again and set BarcodeAr and BarcodeArView up again before start(): start() alone does not restart a disposed context.

Intent Routing

Based on the user's request, load the appropriate reference file before responding:

• Integrating MatrixScan AR from scratch (e.g. "add MatrixScan AR to my web app", "set up BarcodeAr", "show AR highlights on barcodes", "show info annotations", "how to use BarcodeArView on web", "lifecycle or cleanup") → read references/integration.md and follow the instructions there.
• Migrating from BarcodeBatch / BarcodeTracking to BarcodeAr (e.g. "migrate from BarcodeBatch to BarcodeAr", "convert MatrixScan Batch to MatrixScan AR", "replace BarcodeTracking with BarcodeAr") → read references/migration.md and follow the instructions there.

API Usage Policy

Only use APIs that are explicitly documented in the Scandit references below. Do not invent or guess method signatures, parameters, property names, or imports. If unsure whether an API exists or how it is called — or if a compile error occurs — fetch the relevant reference page before responding. Do not tell the user to check the docs themselves. After answering, always include the relevant link so the user can explore further.

Never construct or guess documentation URLs. When you need a specific class or property's API page:

1. First check whether the page you already fetched contains a direct hyperlink to it — topic pages link directly to relevant API symbols.
2. If no direct link was found, fetch the API index (see Full API reference in the table below), extract the actual link from it, and follow that.

URL structures vary across SDK versions and guessing will lead to 404s.

Licence key

Scanning needs a Scandit licence key. For this skill the licence product is sdk and the licence platform is webassembly.

Work through these in order — never block the user on MCP:

1. The Scandit MCP server is connected — call ensure_scanner_setup with product sdk and platforms webassembly, app_identifier (the app's bundle or application id; for web, its production domain, never localhost) and env_var SCANDIT_LICENSE_KEY. Do not run the command it returns. Then call get_license_key with the key's id, from that result or from list_license_keys; if list_license_keys shows the key is not a trial, ask the user before fetching it. Show at most a masked preview in chat; never print a full key.

2. It is not connected — tell the user once that they can connect the remote Scandit MCP server, https://ssl.scandit.com/mcp, in their MCP client, then continue from step 1. Do not edit MCP client configuration yourself.

   Authentication is browser-based, so it is not supported headless or in CI. The server provisions trial keys only; it never creates, revokes, or modifies production licences.

3. The user declines, or has no MCP client — they generate a key themselves at https://ssl.scandit.com (no account yet: https://ssl.scandit.com/dashboard/sign-up?p=test) and paste it in.

Then put the key into the code: write it into the licence-key call in place of the placeholder — the key get_license_key returned, or the one the user pastes or gives you — still showing only a masked preview in chat. Do not search the project, its files or the environment for a key.

References

Direct users to the right resource based on their question:

Topic	Resource
Get Started	Get Started · Simple Sample
Multithreading / COOP+COEP headers	Improve Runtime Performance
Full API reference	BarcodeAr API