Advanced MCP Features

import fs from 'node:fs/promises' import path from 'node:path' import { invariant } from '@epic-web/invariant' import { faker } from '@faker-js/faker' import { Client } from '@modelcontextprotocol/sdk/client/index.js' import { StdioClientTransport } from '@modelcontextprotocol/sdk/client/stdio.js' import { test, expect } from 'vitest' function getTestDbPath() { return `./test.ignored/db.${process.env.VITEST_WORKER_ID}.${Math.random().toString(36).slice(2)}.sqlite` } async function setupClient({ capabilities = {} } = {}) { const EPIC_ME_DB_PATH = getTestDbPath() const dir = path.dirname(EPIC_ME_DB_PATH) await fs.mkdir(dir, { recursive: true }) const client = new Client( { name: 'EpicMeTester', version: '1.0.0', }, { capabilities }, ) const transport = new StdioClientTransport({ command: 'tsx', args: ['src/index.ts'], stderr: 'ignore', env: { ...process.env, EPIC_ME_DB_PATH, }, }) await client.connect(transport) return { client, EPIC_ME_DB_PATH, async [Symbol.asyncDispose]() { await client.transport?.close() // give things a moment to release locks and whatnot await new Promise((r) => setTimeout(r, 100)) await fs.unlink(EPIC_ME_DB_PATH).catch(() => {}) // ignore missing file }, } } test('Tool Definition', async () => { await using setup = await setupClient() const { client } = setup const list = await client.listTools() const [firstTool] = list.tools invariant(firstTool, '🚨 No tools found') expect(firstTool, '🚨 firstTool should be a create_entry tool').toEqual( expect.objectContaining({ name: expect.stringMatching(/^create_entry$/i), description: expect.stringMatching(/^create a new journal entry$/i), inputSchema: expect.objectContaining({ type: 'object', properties: expect.objectContaining({ title: expect.objectContaining({ type: 'string', description: expect.stringMatching(/title/i), }), content: expect.objectContaining({ type: 'string', description: expect.stringMatching(/content/i), }), }), }), }), ) }) test('Tool annotations', async () => { await using setup = await setupClient() const { client } = setup // Check create_entry and create_tag annotations (always enabled) let list = await client.listTools() let toolMap = Object.fromEntries(list.tools.map((t) => [t.name, t])) // Check create_entry annotations const createEntryTool = toolMap['create_entry'] invariant(createEntryTool, '🚨 create_entry tool not found') expect( createEntryTool.annotations, '🚨 create_entry missing annotations', ).toEqual( expect.objectContaining({ destructiveHint: false, openWorldHint: false, }), ) // Check create_tag annotations const createTagTool = toolMap['create_tag'] invariant(createTagTool, '🚨 create_tag tool not found') expect( createTagTool.annotations, '🚨 create_tag missing annotations', ).toEqual( expect.objectContaining({ destructiveHint: false, openWorldHint: false, }), ) // Create a tag and entry to enable other tools const tagResult = await client.callTool({ name: 'create_tag', arguments: { name: 'TestTag', description: 'A tag for testing', }, }) const entryResult = await client.callTool({ name: 'create_entry', arguments: { title: 'Test Entry', content: 'This is a test entry', }, }) // List tools again now that entry and tag exist list = await client.listTools() toolMap = Object.fromEntries(list.tools.map((t) => [t.name, t])) // Check get_entry annotations (read-only) const getEntryTool = toolMap['get_entry'] invariant(getEntryTool, '🚨 get_entry tool not found') expect(getEntryTool.annotations, '🚨 get_entry missing annotations').toEqual( expect.objectContaining({ readOnlyHint: true, openWorldHint: false, }), ) // Check list_entries annotations (read-only) const listEntriesTool = toolMap['list_entries'] invariant(listEntriesTool, '🚨 list_entries tool not found') expect( listEntriesTool.annotations, '🚨 list_entries missing annotations', ).toEqual( expect.objectContaining({ readOnlyHint: true, openWorldHint: false, }), ) // Check update_entry annotations (idempotent) const updateEntryTool = toolMap['update_entry'] invariant(updateEntryTool, '🚨 update_entry tool not found') expect( updateEntryTool.annotations, '🚨 update_entry missing annotations', ).toEqual( expect.objectContaining({ destructiveHint: false, idempotentHint: true, openWorldHint: false, }), ) // Check delete_entry annotations const deleteEntryTool = toolMap['delete_entry'] invariant(deleteEntryTool, '🚨 delete_entry tool not found') expect( deleteEntryTool.annotations, '🚨 delete_entry missing annotations', ).toEqual(expect.objectContaining({ openWorldHint: false })) // Check get_tag annotations (read-only) const getTagTool = toolMap['get_tag'] invariant(getTagTool, '🚨 get_tag tool not found') expect(getTagTool.annotations, '🚨 get_tag missing annotations').toEqual( expect.objectContaining({ readOnlyHint: true, openWorldHint: false, }), ) // Check list_tags annotations (read-only) const listTagsTool = toolMap['list_tags'] invariant(listTagsTool, '🚨 list_tags tool not found') expect(listTagsTool.annotations, '🚨 list_tags missing annotations').toEqual( expect.objectContaining({ readOnlyHint: true, openWorldHint: false, }), ) // Check update_tag annotations (idempotent) const updateTagTool = toolMap['update_tag'] invariant(updateTagTool, '🚨 update_tag tool not found') expect( updateTagTool.annotations, '🚨 update_tag missing annotations', ).toEqual( expect.objectContaining({ destructiveHint: false, idempotentHint: true, openWorldHint: false, }), ) // Check delete_tag annotations (idempotent) const deleteTagTool = toolMap['delete_tag'] invariant(deleteTagTool, '🚨 delete_tag tool not found') expect( deleteTagTool.annotations, '🚨 delete_tag missing annotations', ).toEqual(expect.objectContaining({ openWorldHint: false })) // Check add_tag_to_entry annotations (idempotent) const addTagToEntryTool = toolMap['add_tag_to_entry'] invariant(addTagToEntryTool, '🚨 add_tag_to_entry tool not found') expect( addTagToEntryTool.annotations, '🚨 add_tag_to_entry missing annotations', ).toEqual( expect.objectContaining({ destructiveHint: false, idempotentHint: true, openWorldHint: false, }), ) // Check create_wrapped_video annotations const createWrappedVideoTool = toolMap['create_wrapped_video'] invariant(createWrappedVideoTool, '🚨 create_wrapped_video tool not found') expect( createWrappedVideoTool.annotations, '🚨 create_wrapped_video missing annotations', ).toEqual( expect.objectContaining({ destructiveHint: false, openWorldHint: false, }), ) }) test('Basic tool functionality', async () => { await using setup = await setupClient() const { client } = setup // Test create_entry const entryResult = await client.callTool({ name: 'create_entry', arguments: { title: 'Test Entry', content: 'This is a test entry', }, }) expect(entryResult.content).toBeDefined() expect(Array.isArray(entryResult.content)).toBe(true) expect((entryResult.content as any[]).length).toBeGreaterThan(0) // Test create_tag const tagResult = await client.callTool({ name: 'create_tag', arguments: { name: 'TestTag', description: 'A tag for testing', }, }) expect(tagResult.content).toBeDefined() expect(Array.isArray(tagResult.content)).toBe(true) expect((tagResult.content as any[]).length).toBeGreaterThan(0) // Test basic CRUD operations work const list = await client.listTools() const toolNames = list.tools.map((t) => t.name) expect(toolNames).toContain('create_entry') expect(toolNames).toContain('create_tag') expect(toolNames).toContain('get_entry') expect(toolNames).toContain('get_tag') expect(toolNames).toContain('list_entries') expect(toolNames).toContain('list_tags') expect(toolNames).toContain('update_entry') expect(toolNames).toContain('update_tag') expect(toolNames).toContain('delete_entry') expect(toolNames).toContain('delete_tag') expect(toolNames).toContain('add_tag_to_entry') expect(toolNames).toContain('create_wrapped_video') })