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Blazor LLM Kit ToolCall
Updated on Oct 1, 2026
The ToolCall component shows a tool invocation made by the agent, including the tool name, its input parameters, and the result. It also supports a human-in-the-loop approval flow where users can approve or reject the tool execution before it runs.
Use the component when an agent requests access to an external system such as a database, API, or file store, and you want to give users visibility and control over that action.
Creating Blazor ToolCall
To use the ToolCall component:
- Add the
<TelerikToolCall>tag. - Set the
Labelparameter to the tool name. - Set the
Stateparameter to aToolCallStatevalue that reflects the current execution state. - Set the
Parametersparameter to an object representing the tool inputs. - (optional) Set
ApprovalTextto describe what the tool will do. This text appears whenStateisToolCallState.AwaitingApproval. - (optional) Subscribe to
OnActionto handle approve and reject actions. - (optional) Set
Resultto display the tool output after execution. - (optional) Set
ErrorTextto display an error message whenStateisToolCallState.Error.
Completed ToolCall showing tool name, parameters, and execution metadata
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ToolCall awaiting user approval before execution
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ToolCall API
Get familiar with all ToolCall parameters, states, and events in the ToolCall API Reference.