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toHaveTool

Checks that an MCP server provides a tool with the specified name. This matcher works with MCPStdinSubprocess instances.

Syntax​

await expect(app).toHaveTool(toolName);

Parameters​

  • toolName: The name of the tool to check for

Example​

import { mcpShell } from 'expect-mcp';
import { test, expect } from 'vitest';

test('server provides file operations', async () => {
  const app = mcpShell('node file-server.js');
  await app.initialize();

  await expect(app).toHaveTool('read_file');
  await expect(app).toHaveTool('write_file');

  app.close();
});

Error Messages​

If the tool doesn't exist:

await expect(app).toHaveTool('nonexistent_tool');
// Error: Expected server to have tool "nonexistent_tool", but it was not found.
// Available tools: read_file, write_file, delete_file

See Also​