fix: lazy-load optional ai peer

src/tool-optional-ai.test.ts

@@ -0,0 +1,71 @@
+import { existsSync } from 'node:fs';
+import { readFile } from 'node:fs/promises';
+import { StackOneError } from './utils/error-stackone';
+import { peerDependencies } from '../package.json';
+import { ParameterLocation, type ExecuteConfig, type ToolParameters } from './types';
+
+const builtToolEsm = new URL('../dist/src/tool.mjs', import.meta.url);
+const builtToolCjs = new URL('../dist/src/tool.cjs', import.meta.url);
+const distReady = existsSync(builtToolEsm) && existsSync(builtToolCjs);
+
+const createExecuteConfig = (): ExecuteConfig => ({
+	kind: 'http',
+	method: 'GET',
+	url: 'https://api.example.com/test/{id}',
+	bodyType: 'json',
+	params: [
+		{
+			name: 'id',
+			location: ParameterLocation.PATH,
+			type: 'string',
+		},
+	],
+});
+
+const createParameters = (): ToolParameters => ({
+	type: 'object',
+	properties: { id: { type: 'string', description: 'ID parameter' } },
+});
+
+describe('BaseTool optional ai peer handling', () => {
+	afterEach(() => {
+		vi.resetModules();
+		vi.restoreAllMocks();
+	});
+
+	it('rejects toClaudeAgentSdkTool with StackOneError and install hint when ai is unavailable', async () => {
+		vi.doMock('./utils/try-import', () => ({
+			tryImport: vi.fn(async (moduleName: string, installHint: string) => {
+				if (moduleName === 'ai') {
+					throw new StackOneError(
+						`${moduleName} is not installed. Please install it with: ${installHint}`,
+					);
+				}
+
+				throw new Error(`Unexpected module request: ${moduleName}`);
+			}),
+		}));
+
+		const { BaseTool } = await import('./tool');
+		const tool = new BaseTool('test_tool', 'Test tool', createParameters(), createExecuteConfig());
+
+		await expect(tool.toClaudeAgentSdkTool()).rejects.toBeInstanceOf(StackOneError);
+		await expect(tool.toClaudeAgentSdkTool()).rejects.toThrow(
+			`ai is not installed. Please install it with: npm install ai (requires ${peerDependencies.ai})`,
+		);
+	});
+
+	it.skipIf(!distReady)('keeps the built ESM module free of a top-level ai import', async () => {
+		const builtToolModule = await readFile(builtToolEsm, 'utf8');
+
+		expect(builtToolModule).toContain('tryImport("ai"');
+		expect(builtToolModule).not.toMatch(/^\s*import\s+.*['"]ai['"]/m);
+	});
+
+	it.skipIf(!distReady)('keeps the built CJS module free of a top-level ai require', async () => {
+		const builtToolModule = await readFile(builtToolCjs, 'utf8');
+
+		expect(builtToolModule).toContain('tryImport("ai"');
+		expect(builtToolModule).not.toMatch(/require\(["']ai["']\)/);
+	});
+});

src/tool.ts

@@ -1,4 +1,4 @@
-import { type JSONSchema7 as AISDKJSONSchema, jsonSchema } from 'ai';
+import type { JSONSchema7 as AISDKJSONSchema } from 'ai';
 import type { Tool as AnthropicTool } from '@anthropic-ai/sdk/resources';
 import type { McpSdkServerConfigWithInstance } from '@anthropic-ai/claude-agent-sdk';
 import type { ChatCompletionFunctionTool } from 'openai/resources/chat/completions';
@@ -248,7 +248,11 @@ export class BaseTool {
 			args: Record<string, unknown>,
 		) => Promise<{ content: Array<{ type: 'text'; text: string }> }>;
 	}> {
-		const inputSchema = jsonSchema(this.toJsonSchema());
+		const ai = await tryImport<typeof import('ai')>(
+			'ai',
+			`npm install ai (requires ${peerDependencies.ai})`,
+		);
+		const inputSchema = ai.jsonSchema(this.toJsonSchema());
 		const execute = this.execute.bind(this);
 
 		return {