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Tools

Tools API Reference

Tool definitions, React renderers, status helpers, and toolkits for exposing callable app capabilities to assistant-ui chat models.

Use these APIs when your assistant needs to call application code, render a custom tool result, or expose tool state inside a React UI.

Toolkits are the current registration API. Tool rendering and status are independent of the tool's execution location and apply to frontend, backend, human, and MCP tools.

Tools({ toolkit })
ScopeEntire assistant subtree below the mount point
LifecycleTied to the runtime / provider tree
Typical useApp-wide tools, dynamic scoped tools, MCP merging, tools defined alongside the runtime
Stable referencePass a stable toolkit (module scope or useMemo)

useAssistantTool, makeAssistantTool, useAssistantToolUI, and makeAssistantToolUI are deprecated compatibility APIs. See Migrating Tools to Toolkits.

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