MCP TypeScript SDKBLOCK
The official TypeScript SDK for Model Context Protocol servers and clients
Overview
From the repository's own README, as read at the audited commit. Badges and raw HTML are left out.
Important Note This is an unofficial fork upgraded to Zod V4. You can check the changes directly on the github repository
ORIGINAL version
This fork
Table of Contents
- Overview
- Installation
- Quickstart
- What is MCP?
- Core Concepts
- Server
- Resources
- Tools
- Prompts
- Completions
- Sampling
- Running Your Server
- stdio
- Streamable HTTP
- Testing and Debugging
- Examples
- Echo Server
- SQLite Explorer
- Advanced Usage
- Dynamic Servers
- Low-Level Server
- Writing MCP Clients
- Proxy Authorization Requests Upstream
- Backwards Compatibility
- Documentation
- Contributing
- License
Overview
The Model Context Protocol allows applications to provide context for LLMs in a standardized way, separating the concerns of providing context from the actual LLM interaction. This TypeScript SDK implements the full MCP specification, making it easy to:
- Build MCP clients that can connect to any MCP server
- Create MCP servers that expose resources, prompts and tools
- Use standard transports like stdio and Streamable HTTP
- Handle all MCP protocol messages and lifecycle events
Installatio
001026ed50bfOBSERVED · 2026-10-12Connect
Built from this server's own package name, version and transport as found in its source — not copied from anyone's documentation, so it cannot drift against a page we do not control. Replace the environment placeholders with a token scoped to the least it needs.
claude mcp add modelcontextprotocol-sdk --env MCP_AUTH_PORT=${MCP_AUTH_PORT} -- npx -y @alcyone-labs/[email protected]{
"mcpServers": {
"modelcontextprotocol-sdk": {
"command": "npx",
"args": [
"-y",
"@alcyone-labs/[email protected]"
],
"env": {
"MCP_AUTH_PORT": "${MCP_AUTH_PORT}"
}
}
}
}Exposed tools (11)
10 read · 1 write · 0 destructive.
| Tool | Risk | Description |
|---|---|---|
collect-user-info | read | A tool that collects user information through elicitation |
complex-tool | read | A tool with complex schema |
get_weather | read | |
greet | read | A simple greeting tool |
lib.rs | read | Library exports |
list-files | read | |
main.rs | read | Primary application entry point |
multi-greet | read | A tool that sends different greetings with delays between them |
start-notification-stream | write | Starts sending periodic notifications |
strict-tool | read | A tool with strict schema |
test-tool | read | A test tool |
Trust audit
BLOCKgrade D · trust 69/100 Do not install this without reading the findings. The audit found something that could harm you or your machine.
| Layer | What it checks | Result |
|---|---|---|
| L0 | Provenance & inventory | PASS |
| L1 | Static analysis of the code | FAIL |
| L2 | Instruction surface (what it tells the agent) | PASS |
| L3 | Class-specific surface | PASS |
| L4 | Behavioural (sandbox) | SKIPPED |
What the source does
- Filesystem
- none-observed
- Network
- declared (3 observation(s))
- Shell
- none-observed
- Dependencies
- not all pinned
- Secrets in source
- none-found
Findings (21)
: /* list inspired by the default env inheritance of sudo */
.git-blame-ignore-revs
exec(command, (error) => {console.log(`Using resumption token: ${notificationsToolLastEventId || 'none'}`);console.log(`Updated resumption token: ${event}`);import { Client } from '../../client/index.js';import { StreamableHTTPClientTransport } from '../../client/streamableHttp.js';} from '../../types.js';
import { Client } from '../../client/index.js';import { StreamableHTTPClientTransport } from '../../client/streamableHttp.js';const CALLBACK_URL = `http://localhost:${CALLBACK_PORT}/callback`;redirect_uris: [CALLBACK_URL],
CALLBACK_URL,
resourceBaseUrl = new URL(`http://127.0.0.1:${addr.port}`);resourceBaseUrl = new URL(`http://127.0.0.1:${addr.port}`);resourceBaseUrl = new URL(`http://127.0.0.1:${addr.port}`);authBaseUrl = new URL(`http://127.0.0.1:${addr.port}`);resourceBaseUrl = new URL(`http://127.0.0.1:${addr.port}`);atob(val);
ajv, content-type, cors, cross-spawn, eventsource, eventsource-parser, express, express-rate-limit
system use found in code, not declared in the description
Gates applied: no_behavioural_pass.
001026ed50bffull audit observations/trust-audit/mcp-server/alcyone-labs__mcp-typescript-sdk.json · Report an issue / request a re-scanAudit history
Every audit this server has had. A grade with a past is a grade somebody is still checking.
| Date | Source | Verdict | Grade | Score | Change |
|---|---|---|---|---|---|
| 2026-10-12 | 001026ed50bf | BLOCK | D | 69 | first audit |
Questions
What is the @alcyone-labs/modelcontextprotocol-sdk MCP server?
The official TypeScript SDK for Model Context Protocol servers and clients
What tools does @alcyone-labs/modelcontextprotocol-sdk expose?
11 in total: 10 read-only, 1 that write, and 0 that can delete or overwrite. Every one is listed on this page with its risk.
Is @alcyone-labs/modelcontextprotocol-sdk safe to connect to an agent?
No — not without reading the findings first. The audit graded it D (69/100) and found 1 critical or high issue in the source. Each one is listed on this page with the file and line it is on.
What credentials does @alcyone-labs/modelcontextprotocol-sdk need?
It reads MCP_AUTH_PORT from the environment. Give it a token scoped to the least it needs — an agent that can be talked into calling a tool can be talked into calling it with your credentials.
How does @alcyone-labs/modelcontextprotocol-sdk run?
It speaks sse, stdio and streamable-http, so it runs as a local process your client starts. It is published on npm as @alcyone-labs/modelcontextprotocol-sdk at 1.16.0.
How current is this page?
The grade is for one exact copy of the source (001026ed50bf), read on 2026-10-12. The repository is watched and re-audited when it changes.