# 5.9 Overlays

> Contract 2.0.0 · package sha256 `a857eca95b35921109faf997094bb4192f12527d9d0fcd4be7e97f06425bad6e` · generated from `examples/section-5/5.09-overlays.ts` by `services/onsite-scripter/scripts/build-contract-docs.mjs`; edit the source, not this file.

Imports: values (`has`, `validate`, the `Holo*Error` classes, the pure helpers) from `@holostep-configurators/runtime-client`, types from `@holostep-configurators/runtime-client/contract`, `/math` and `/testing` names from those entries; `boot` from the runtime module the root's `loadRuntimeAtFloor` resolves to. A type your page defines is your app's: declare it there, never import it from the package.

```ts
import type { Session } from '@holostep-configurators/runtime-client/contract';
declare const session: Session;
declare const signal: AbortSignal;
session.overlays.dimensions({ role: 'product' }, { axes: ['width', 'height', 'depth'], format: (m) => `${Math.round(m * 1000).toLocaleString('en').replace(/,/g, ' ')} mm` });
```

Back to [the examples](README.md) · [llms.txt](../llms.txt)