feat: add tool factory (#663)

.changeset/lemon-windows-fetch.md

+---
+"llamaindex": patch
+---
+
+feat: add tool factory

packages/core/src/tools/ToolFactory.ts

+import type { BaseTool } from "../types.js";
+import { WikipediaTool } from "./WikipediaTool.js";
+
+enum Tools {
+  Wikipedia = "wikipedia.WikipediaToolSpec",
+}
+
+type ToolConfig = { [key in Tools]: Record<string, any> };
+
+export class ToolFactory {
+  private static async createTool(
+    key: Tools,
+    options: Record<string, any>,
+  ): Promise<BaseTool> {
+    if (key === Tools.Wikipedia) {
+      const tool = new WikipediaTool();
+      return tool;
+    }
+
+    throw new Error(
+      `Sorry! Tool ${key} is not supported yet. Options: ${options}`,
+    );
+  }
+
+  public static async createTools(config: ToolConfig): Promise<BaseTool[]> {
+    const tools: BaseTool[] = [];
+    for (const [key, value] of Object.entries(config as ToolConfig)) {
+      const tool = await ToolFactory.createTool(key as Tools, value);
+      tools.push(tool);
+    }
+    return tools;
+  }
+}

packages/core/src/tools/index.ts

 export * from "./QueryEngineTool.js";
+export * from "./ToolFactory.js";
 export * from "./WikipediaTool.js";
 export * from "./functionTool.js";
 export * from "./types.js";