feat(ai): export ToolCallState type

.changeset/export-tool-call-state-type.md

@@ -0,0 +1,5 @@
+---
+'ai': patch
+---
+
+Export `ToolCallState` type from the `ai` package. This is a string union type representing all possible states of a tool call invocation (`input-streaming`, `input-available`, `approval-requested`, `approval-responded`, `output-available`, `output-error`, `output-denied`). It can be used to type helper functions, component props, and other constructs that work with tool call states.

content/docs/07-reference/01-ai-sdk-core/31-ui-message.mdx

@@ -117,6 +117,21 @@ type ReasoningUIPart = {
 };
 ```
 
+### `ToolCallState`
+
+A type representing the possible states of a tool invocation within a `ToolUIPart`.
+
+```typescript
+type ToolCallState =
+  | 'input-streaming'
+  | 'input-available'
+  | 'approval-requested'
+  | 'approval-responded'
+  | 'output-available'
+  | 'output-error'
+  | 'output-denied';
+```
+
 ### `ToolUIPart`
 
 A tool part of a message that represents tool invocations and their results.

packages/ai/src/ui/index.ts

@@ -57,6 +57,7 @@ export {
   type SourceUrlUIPart,
   type StepStartUIPart,
   type TextUIPart,
+  type ToolCallState,
   type ToolUIPart,
   type UIDataTypes,
   type UIMessage,

packages/ai/src/ui/ui-messages.test-d.ts

@@ -0,0 +1,13 @@
+import { expectTypeOf } from 'vitest';
+import { ToolCallState } from './ui-messages';
+
+// test ToolCallState type
+expectTypeOf<ToolCallState>().toEqualTypeOf<
+  | 'input-streaming'
+  | 'input-available'
+  | 'approval-requested'
+  | 'approval-responded'
+  | 'output-available'
+  | 'output-error'
+  | 'output-denied'
+>();

packages/ai/src/ui/ui-messages.ts

@@ -263,6 +263,26 @@ export function isDataUIPart<DATA_TYPES extends UIDataTypes>(
   return part.type.startsWith('data-');
 }
 
+/**
+ * The possible states of a tool call invocation.
+ *
+ * - `input-streaming`: The tool call input is still being streamed.
+ * - `input-available`: The tool call input is fully available.
+ * - `approval-requested`: The tool call requires user approval before execution.
+ * - `approval-responded`: The user has responded to the approval request.
+ * - `output-available`: The tool call has completed and output is available.
+ * - `output-error`: The tool call has completed with an error.
+ * - `output-denied`: The tool call was denied by the user.
+ */
+export type ToolCallState =
+  | 'input-streaming'
+  | 'input-available'
+  | 'approval-requested'
+  | 'approval-responded'
+  | 'output-available'
+  | 'output-error'
+  | 'output-denied';
+
 /**
  * A UI tool invocation contains all the information needed to render a tool invocation in the UI.
  * It can be derived from a tool without knowing the tool name, and can be used to define