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Defined in: server/FastMCP.ts:98

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Properties

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auth?

optional auth?: AuthCheck;
Defined in: server/FastMCP.ts:124

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description

description: string;
Defined in: server/FastMCP.ts:102

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disabled?

optional disabled?: boolean;
Defined in: server/FastMCP.ts:121 When true the tool is hidden from listTools and cannot be invoked via tools/call.

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input?

optional input?: StandardSchemaV1<unknown, unknown>;
Defined in: server/FastMCP.ts:104 Standard Schema validator for the tool’s input arguments. Used for runtime validation.

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inputSchema?

optional inputSchema?: Record<string, unknown>;
Defined in: server/FastMCP.ts:110 Explicit JSON Schema advertised to clients as inputSchema. Overrides auto-generation from input. Use when you need JSON Schema features beyond what your validator auto-generates (e.g. examples, $comment, per-property descriptions, or custom annotations).

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name

name: string;
Defined in: server/FastMCP.ts:99

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output?

optional output?: StandardSchemaV1<unknown, unknown>;
Defined in: server/FastMCP.ts:112 Standard Schema validator for the tool’s return value. Validated before result conversion.

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outputSchema?

optional outputSchema?: Record<string, unknown>;
Defined in: server/FastMCP.ts:117 Explicit JSON Schema advertised to clients as outputSchema. Overrides auto-generation from output. Use when you need JSON Schema features beyond what your validator auto-generates.

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tags?

optional tags?: string[];
Defined in: server/FastMCP.ts:123 Arbitrary tags for server-side filtering.

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timeout?

optional timeout?: number;
Defined in: server/FastMCP.ts:119 Execution timeout in milliseconds. No timeout by default.

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title?

optional title?: string;
Defined in: server/FastMCP.ts:101 Human-readable display name shown in UIs. Takes precedence over name for display purposes.

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ui?

optional ui?: UiToolMeta;
Defined in: server/FastMCP.ts:126 Apps extension — links this tool to a UI resource and controls visibility.