Method validateToolInput

src/server/mcp.ts:258–282

* Validates tool input arguments against the tool's input schema.

(tool: Tool, args: Args, toolName: string)

     * Validates tool input arguments against the tool's input schema.
     */
    private async validateToolInput<
        Tool extends RegisteredTool,
        Args extends Tool['inputSchema'] extends infer InputSchema
            ? InputSchema extends AnySchema
                ? SchemaOutput<InputSchema>
                : undefined
            : undefined
    >(tool: Tool, args: Args, toolName: string): Promise<Args> {
        if (!tool.inputSchema) {
            return undefined as Args;
        }

        // Try to normalize to object schema first (for raw shapes and object schemas)
        // If that fails, use the schema directly (for union/intersection/etc)
        const inputObj = normalizeObjectSchema(tool.inputSchema);
        const schemaToParse = inputObj ?? (tool.inputSchema as AnySchema);
        const parseResult = await safeParseAsync(schemaToParse, args);
        if (!parseResult.success) {
            const error = 'error' in parseResult ? parseResult.error : 'Unknown error';
            const errorMessage = getParseErrorMessage(error);
            throw new McpError(ErrorCode.InvalidParams, `Input validation error: Invalid arguments for tool ${toolName}: ${errorMessage}`);
        }

        return parseResult.data as unknown as Args;
    }

    /**
     * Validates tool output against the tool's output schema.