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

# Remaining SDK types grouped into submodules

> The engine, protocol, internal, and (Python) utils groups join the existing submodules, and several types move out of the root SDK into their submodule with the root export removed.

## What changed

The root SDK surface continues to be grouped into named submodules. This slice adds the `engine`, `protocol`, and `internal` groups (plus a Python `utils` group), and moves the remaining types into their submodule. For these moves the root export is removed: the type is importable only from its submodule.

| Group    | Node               | Python         | Rust                |
| -------- | ------------------ | -------------- | ------------------- |
| engine   | `iii-sdk/engine`   | `iii.engine`   | `iii_sdk::engine`   |
| protocol | `iii-sdk/protocol` | `iii.protocol` | `iii_sdk::protocol` |
| internal | `iii-sdk/internal` | `iii.internal` | n/a                 |
| utils    | n/a                | `iii.utils`    | n/a                 |

## Moved symbols

| Group          | Symbols                                                                                                                                 |
| -------------- | --------------------------------------------------------------------------------------------------------------------------------------- |
| engine         | `EngineFunctions`, `EngineTriggers`, `RemoteFunctionHandler`                                                                            |
| protocol       | `MessageType`, the `Register*Message` and `Register*Input` types, `TriggerRequest`, and the Rust-only `FunctionMessage` and `ErrorBody` |
| internal       | `InternalHttpRequest`                                                                                                                   |
| utils (Python) | `extract_request_format`, `extract_response_format`, `python_type_to_format`                                                            |
| runtime        | `IIIConnectionState` now joins the runtime group                                                                                        |

Per-language differences are respected: a symbol that does not exist in a language is not added there.

`TriggerActionVoid` (Python) is also grouped under `iii.trigger`, but it stays exported from the package root as the companion to `TriggerActionEnqueue`, so it is reachable from both `iii` and `iii.trigger`.

## Migration

Import these types from their submodule. The root path no longer exports them.

```ts theme={"theme":{"light":"catppuccin-latte","dark":"dark-plus"}}
// Node
import { RegisterTriggerInput } from 'iii-sdk/protocol'
import { EngineFunctions } from 'iii-sdk/engine'
```

```python theme={"theme":{"light":"catppuccin-latte","dark":"dark-plus"}}
# Python
from iii.protocol import TriggerRequest
from iii.utils import extract_request_format
```

```rust theme={"theme":{"light":"catppuccin-latte","dark":"dark-plus"}}
// Rust
use iii_sdk::protocol::TriggerRequest;
use iii_sdk::engine::EngineFunctions;
```

## Note on the earlier submodule slice

The first submodule slice (`errors`, `channel`, `trigger`, `runtime`) and the groups in this slice, along with the types extracted into `@iii-dev/helpers`, all remove the root export in 0.20.0. Use the submodule and helpers paths for everything; the old root paths no longer work in this release.

## Why

Grouping the protocol, engine, and internal types out of the root keeps the worker and runtime API at the top level and moves the low-level surface behind clear, navigable paths.