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

# Best Practices

> Getting good behaviour out of a desktop integration

## Put inference in the utility host

`RpcBackend` forwards to the utility process; `NativeBackend` loads the addon in the current
one. Use the host for anything heavy, or a model load blocks the main process and the window
stops responding.

## Unpack the natives

Everything under `node_modules/@runanywhere/*/prebuilds/` has to be `asarUnpack`ed, both by
extension and by the whole tree. The tree rule is what covers QHexRT's `libqnnhtpv81.cat`,
whose absence reads as a corrupt model rather than a packaging fault.

## Read capabilities, do not assume

```ts theme={null}
const capabilities = await RunAnywhere.capabilities()
```

Generated from packaging facts about the linked addon. On `win32-arm64` only QHexRT loads, with
no CPU fallback, so vision, segmentation, and speech are unavailable there. Check before
putting a feature in a menu.

## Offer pause and resume

Download control exists only on Electron. A user closing a laptop lid mid-download should not
lose four gigabytes.

```ts theme={null}
const stalled = await RunAnywhere.models.interrupted()
```

Call this on launch and offer to continue.

## Show a delete plan

```ts theme={null}
const plan = await RunAnywhere.storage.deletePlan()
```

Show what would go before deleting, rather than deleting and reporting afterwards. Nothing else
in the SDK family can do this.

## Use residency policy with several models

A chat model and a voice session compete. Without a policy, one evicts the other on every turn
and the user waits through a reload each time.

## Close sessions on window close, not only on quit

```ts theme={null}
win.on('closed', () => void session?.close())
app.on('before-quit', () => void session?.close())
```

Closing a window does not end the process. A session tied only to quit keeps the microphone
live after the user thinks they stopped.

## Validate tool arguments

Tool executors here have the filesystem, child processes, and the network with no CORS. A model
choosing which file to read is a model choosing which file to read. Confine paths to a
directory you picked, and never build a shell string from model output.

## Batch what crosses the bridge

Token deltas are small enough to forward individually. Audio chunks are not. Send audio once per
chunk and let the renderer schedule playback against a running clock.

## Send error codes, not error objects

Structured clone drops the prototype, so an `SDKException` sent to the renderer arrives as a
plain object and `instanceof` fails. Forward `code` and `message` explicitly.

## Size the load for the machine

A desktop can afford a larger `contextLength` and higher `threads` than a phone. Both still cost
memory, so read what the machine has rather than hardcoding numbers that work on yours.

## Sign your Windows build

The published installers carry no Authenticode certificate, so SmartScreen warns on first run.
If you ship your own build, signing it is the difference between a user proceeding and not.