smartagent/test/test.mcp.ts

import { expect, tap } from '@git.zone/tstest/tapbundle';
import {
  createMcpTools,
  formatMcpToolResult,
  sanitizeMcpToolName,
  type IMcpClientLike,
} from '../ts_mcp/index.js';

interface IFakeMcpClientState {
  calls: Array<{ name: string; arguments?: Record<string, unknown> }>;
  closed: boolean;
}

const createFakeMcpClient = (
  toolName: string,
  responsePrefix: string,
  state: IFakeMcpClientState,
): IMcpClientLike => ({
  listTools: async () => ({
    tools: [
      {
        name: toolName,
        description: `Runs ${toolName}`,
        inputSchema: {
          type: 'object',
          properties: {
            value: { type: 'string' },
          },
          required: ['value'],
        },
      },
    ],
  } as any),
  callTool: async (params) => {
    state.calls.push(params);
    return {
      content: [
        {
          type: 'text',
          text: `${responsePrefix}: ${String(params.arguments?.value ?? '')}`,
        },
      ],
      structuredContent: {
        ok: true,
      },
    } as any;
  },
  close: async () => {
    state.closed = true;
  },
});

tap.test('sanitizeMcpToolName should produce AI SDK-safe tool names', async () => {
  expect(sanitizeMcpToolName('read file/path')).toEqual('read_file_path');
  expect(sanitizeMcpToolName('123-start')).toEqual('_123-start');
  expect(sanitizeMcpToolName('***', 'fallback')).toEqual('fallback');
});

tap.test('createMcpTools should expose prefixed tools for multiple MCP servers', async () => {
  const firstState: IFakeMcpClientState = { calls: [], closed: false };
  const secondState: IFakeMcpClientState = { calls: [], closed: false };

  const mcpTools = await createMcpTools({
    servers: {
      'server one': {
        type: 'client',
        client: createFakeMcpClient('echo tool', 'first', firstState),
      },
      'server/two': {
        type: 'client',
        client: createFakeMcpClient('echo tool', 'second', secondState),
      },
    },
  });

  expect(Object.keys(mcpTools.tools).sort()).toEqual([
    'server_one__echo_tool',
    'server_two__echo_tool',
  ]);
  expect(mcpTools.toolNameMap.server_one__echo_tool).toEqual({
    serverName: 'server one',
    toolName: 'echo tool',
  });

  const output = await (mcpTools.tools.server_one__echo_tool as any).execute({ value: 'hello' });
  expect(output).toInclude('first: hello');
  expect(output).toInclude('Structured content');
  expect(firstState.calls).toEqual([
    {
      name: 'echo tool',
      arguments: { value: 'hello' },
    },
  ]);

  await mcpTools.close();
  expect(firstState.closed).toBeTrue();
  expect(secondState.closed).toBeTrue();
});

tap.test('createMcpTools should support paginated tool discovery and custom formatting', async () => {
  const calls: Array<{ name: string; arguments?: Record<string, unknown> }> = [];
  const client: IMcpClientLike = {
    listTools: async (params) => ({
      tools: [
        {
          name: params?.cursor ? 'second tool' : 'first tool',
          inputSchema: { type: 'object' },
        },
      ],
      nextCursor: params?.cursor ? undefined : 'next',
    } as any),
    callTool: async (params) => {
      calls.push(params);
      return { content: [{ type: 'text', text: 'ok' }] } as any;
    },
  };

  const mcpTools = await createMcpTools({
    servers: {
      only: { type: 'client', client },
    },
    formatResult: (_result, context) => context.exposedToolName,
  });

  expect(Object.keys(mcpTools.tools).sort()).toEqual(['first_tool', 'second_tool']);
  const output = await (mcpTools.tools.second_tool as any).execute('ignored');
  expect(output).toEqual('second_tool');
  expect(calls).toEqual([
    {
      name: 'second tool',
      arguments: {},
    },
  ]);
});

tap.test('formatMcpToolResult should handle MCP result shapes', async () => {
  expect(formatMcpToolResult({ toolResult: { ok: true } } as any)).toEqual({ ok: true });
  expect(formatMcpToolResult({ content: [{ type: 'text', text: 'failed' }], isError: true } as any)).toInclude(
    'MCP tool returned an error',
  );
});

export default tap.start();