/**
* End-to-end MCP server tests.
*
* These tests connect a real MCP client to a real server instance via the
* in-memory transport and perform actual tool calls over MCP protocol.
*/
import { describe, it, expect, vi, beforeEach, afterEach } from 'vitest';
import { Client } from '@modelcontextprotocol/sdk/client';
import { InMemoryTransport } from '@modelcontextprotocol/sdk/inMemory';
import { createMcpServer } from '../server/index';
import type { ServerContext } from '../types/context';
const originalFetch = globalThis.fetch;
function createTestContext(overrides?: Partial<ServerContext>): ServerContext {
return {
apiKey: 'test-api-key',
account: {
id: 'user_test_123',
name: 'Test User',
email: 'test@example.com',
},
app: {
name: 'mcp-server-neon',
transport: 'stdio',
environment: 'development',
version: 'test',
},
...overrides,
};
}
async function withConnectedClient<T>(
context: ServerContext,
run: (client: Client) => Promise<T>,
): Promise<T> {
const server = createMcpServer(context);
const client = new Client({ name: 'test-client', version: '1.0.0' });
const [clientTransport, serverTransport] =
InMemoryTransport.createLinkedPair();
await server.connect(serverTransport);
await client.connect(clientTransport);
try {
return await run(client);
} finally {
await client.close();
await server.close();
}
}
describe('MCP server e2e tool calls', () => {
beforeEach(() => {
globalThis.fetch = vi.fn();
});
afterEach(() => {
globalThis.fetch = originalFetch;
});
it('lists docs tools through MCP listTools', async () => {
await withConnectedClient(createTestContext(), async (client) => {
const result = await client.listTools();
const toolNames = result.tools.map((tool) => tool.name);
expect(toolNames).toContain('list_docs_resources');
expect(toolNames).toContain('get_doc_resource');
});
});
it('calls list_docs_resources through MCP protocol', async () => {
const mockIndex =
'# Neon Docs\n- [AI Concepts](https://neon.com/docs/ai/ai-concepts.md)';
vi.mocked(globalThis.fetch).mockResolvedValue(
new Response(mockIndex, { status: 200 }),
);
await withConnectedClient(createTestContext(), async (client) => {
const result = await client.callTool({
name: 'list_docs_resources',
arguments: { params: {} },
});
expect(result.isError).not.toBe(true);
expect(result.content[0]).toMatchObject({
type: 'text',
});
if (result.content[0].type === 'text') {
expect(result.content[0].text).toContain('AI Concepts');
}
});
});
it('calls get_doc_resource and auto-appends .md through MCP protocol', async () => {
vi.mocked(globalThis.fetch).mockResolvedValue(
new Response('# Prisma Guide\n\nUse Prisma with Neon.', { status: 200 }),
);
await withConnectedClient(createTestContext(), async (client) => {
const result = await client.callTool({
name: 'get_doc_resource',
arguments: { params: { slug: 'docs/guides/prisma' } },
});
expect(result.isError).not.toBe(true);
expect(vi.mocked(globalThis.fetch)).toHaveBeenCalledWith(
'https://neon.com/docs/guides/prisma.md',
);
expect(result.content[0].type).toBe('text');
});
});
it('returns MCP tool error content for invalid slug', async () => {
await withConnectedClient(createTestContext(), async (client) => {
const result = await client.callTool({
name: 'get_doc_resource',
arguments: { params: { slug: 'https://evil.example/bad' } },
});
expect(result.isError).toBe(true);
expect(result.content[0].type).toBe('text');
if (result.content[0].type === 'text') {
expect(result.content[0].text).toContain(
'Invalid doc slug: absolute URLs are not allowed',
);
}
});
});
it('enforces read-only filtering at MCP tool registry level', async () => {
await withConnectedClient(
createTestContext({
readOnly: true,
}),
async (client) => {
const result = await client.listTools();
const toolNames = result.tools.map((tool) => tool.name);
expect(toolNames).toContain('list_docs_resources');
expect(toolNames).toContain('get_doc_resource');
expect(toolNames).not.toContain('create_project');
},
);
});
});
