# ClientToolResult

> Tracon documentation. Tracon is a .NET package family that adds a control
> plane on Microsoft Agent Framework, published as NuGet packages that run
> inside your own ASP.NET Core application.
>
> Page: https://tracon.dev/http-api/schemas/clienttoolresult/
> Summary: OpenAPI request or response schema for ClientToolResult, including required fields, defaults, constraints, and linked nested types.

[← All HTTP schemas](/http-api/schemas/)

The result of a single client-side tool call, sent back so the run can
continue.

**Shape:** `object`

| Property | Required | Type | Description | Rules |
|---|---|---|---|---|
| `callId` | yes | `string` | Identifier of the pending call this result answers. Matches the `FunctionCallContent.CallId` the run response carried. | — |
| `result` | no | `string` | The tool's result, given to the model as plain text. Required unless `ErrorMessage` is given. | — |
| `errorMessage` | no | `string` | A message describing why the client-side call failed, given to the model instead of `Result`. | — |