# MessagePartRuntime
URL: /docs/api-reference/runtimes/message-part-runtime

Hook for accessing message part state within parts.

`useAui` (Message Part Actions) \[#useaui-message-part-actions]

Access message part actions via `useAui`:

```tsx
import { useAui } from "@assistant-ui/react";

const aui = useAui();

// Add a tool result to a tool-call message part
aui.part().addToolResult({ result: "Tool output" });

// Resume an interrupted tool call
aui.part().resumeToolCall({ approved: true });
```

<ParametersTable />

`useAuiState` (Message Part State) \[#useauistate-message-part-state]

Access the message part state reactively:

```tsx
import { useAuiState } from "@assistant-ui/react";

const status = useAuiState((s) => s.part.status);
const type = useAuiState((s) => s.part.type);
```

For imperative access, use `useAui`:

```tsx
import { useAui } from "@assistant-ui/react";

const aui = useAui();
const partState = aui.part().getState();
```

<ParametersTable />