import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
import { z, ZodError, ZodRawShape, ZodType } from "zod";
import { BotConnection } from './bot-connection.js';
type McpResponse = {
content: { type: "text"; text: string }[];
isError?: boolean;
[key: string]: unknown;
};
export class ToolFactory {
constructor(
private server: McpServer,
private connection: BotConnection
) {}
registerTool(
name: string,
description: string,
schema: Record<string, unknown>,
// eslint-disable-next-line @typescript-eslint/no-explicit-any
executor: (args: any) => Promise<McpResponse>
): void {
this.server.tool(name, description, schema, async (args: unknown): Promise<McpResponse> => {
const connectionCheck = await this.connection.checkConnectionAndReconnect();
if (!connectionCheck.connected) {
return {
content: [{ type: "text", text: connectionCheck.message! }],
isError: true
};
}
try {
const parsedArgs = this.shouldValidateSchema(schema)
? this.parseArgs(schema as ZodRawShape, args)
: args;
return await executor(parsedArgs);
} catch (error) {
return this.createErrorResponse(error as Error);
}
});
}
createResponse(text: string): McpResponse {
return {
content: [{ type: "text", text }]
};
}
createErrorResponse(error: Error | string): McpResponse {
const errorMessage = error instanceof Error ? error.message : error;
return {
content: [{ type: "text", text: `Failed: ${errorMessage}` }],
isError: true
};
}
private shouldValidateSchema(schema: Record<string, unknown>): boolean {
const values = Object.values(schema);
if (values.length === 0) {
return true;
}
return values.every((value) => value instanceof ZodType);
}
private parseArgs(schema: ZodRawShape, args: unknown): unknown {
try {
return z.object(schema).passthrough().parse(args ?? {});
} catch (error) {
if (error instanceof ZodError) {
throw new Error(this.formatZodError(error));
}
throw error;
}
}
private formatZodError(error: ZodError): string {
const details = error.issues
.map((issue) => {
const path = issue.path.length > 0 ? `${issue.path.join('.')}: ` : '';
return `${path}${issue.message}`;
})
.join('; ');
return `Invalid tool arguments: ${details}`;
}
}
