Atlas / MCP servers / mjknowles / Matrix

MatrixBLOCK

Name: Matrix
Author: mjknowles

mcp/mjknowles/matrix

MCP server by mjknowles · homeserver · matrix · matrix homeserver · Audited 2026-10-08

⚑ Report / re-scan Source ↗

MCP Server for a Matrix home server integration; chat, manage rooms, etc.

Verdict

BLOCK

Grade

Trust score

69 /100

Exposed tools

20 15r · 5w · 0d

Transport

streamable-http

License

MIT

Stars

Overview

From the repository's own README, as read at the audited commit. Badges and raw HTML are left out.

A comprehensive Model Context Protocol (MCP) server that provides secure access to Matrix homeserver functionality. Built with TypeScript, this server enables MCP clients to interact with Matrix rooms, messages, users, and more through a standardized interface.

Features

🔐 OAuth 2.0 Authentication with token exchange support
📱 15 Matrix Tools organized by functionality tiers
🏠 Multi-homeserver Support with configurable endpoints
🔄 Real-time Operations with ephemeral client management
🚀 Production Ready with comprehensive error handling
📊 Rich Responses with detailed Matrix data

Quick Start

Prerequisites

Node.js 20+ and npm
Matrix homeserver access (Synapse, Dendrite, etc.)
MCP client (Claude Desktop, VS Code with MCP extension, etc.)

Installation

# Clone the repository
git clone 
cd matrix-mcp-server

# Install dependencies
npm install

# Build the project
npm run build

# Configure environment
cp .env.example .env
# Edit .env with your settings

# Start the server
npm start

Development Mode

# Start with hot reload (OAuth disabled for easier testing)
npm run dev

# Or start with OAuth enabled
ENABLE_OAUTH=true npm run dev

Available Tools

📖 Tier 0: Read-Only Tools

Room Tools

`list-joined-rooms` - Get all rooms the user has joined

No parameters required
Returns room names, IDs, and member counts

`get-room-info` - Get detailed room information

roomId (string): Matrix room ID (e.g., !roomid:domain.com)
Returns name, topic, settings, creator, and member count

`get-room-members` - List all members in a room
roomId (string): Matrix room ID
Returns display names and user IDs of joined members

Message Tools

`get-room-messages` - Retrieve recent messages from a room

roomId (string): Matrix room ID
limit (number, default: 20): Maxim

Read from source at commit 152607b1bc05OBSERVED · 2026-10-08

Connect

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-code

claude mcp add matrix-mcp-server --env ENABLE_OAUTH=${ENABLE_OAUTH} --env ENABLE_TOKEN_EXCHANGE=${ENABLE_TOKEN_EXCHANGE} --env IDP_AUTHORIZATION_URL=${IDP_AUTHORIZATION_URL} --env IDP_TOKEN_URL=${IDP_TOKEN_URL} -- npx -y [email protected]

claude-desktop

{
  "mcpServers": {
    "matrix-mcp-server": {
      "command": "npx",
      "args": [
        "-y",
        "[email protected]"
      ],
      "env": {
        "ENABLE_OAUTH": "${ENABLE_OAUTH}",
        "ENABLE_TOKEN_EXCHANGE": "${ENABLE_TOKEN_EXCHANGE}",
        "IDP_AUTHORIZATION_URL": "${IDP_AUTHORIZATION_URL}",
        "IDP_TOKEN_URL": "${IDP_TOKEN_URL}"
      }
    }
  }
}

Exposed tools (20)

15 read · 5 write · 0 destructive.

Tool	Risk	Description
`create-room`	write
`get-all-users`	read
`get-direct-messages`	read
`get-messages-by-date`	read
`get-my-profile`	read
`get-notification-counts`	read
`get-room-info`	read
`get-room-members`	read
`get-room-messages`	read
`get-user-profile`	read
`identify-active-users`	read
`invite-user`	read
`join-room`	read
`leave-room`	read
`list-joined-rooms`	read
`search-public-rooms`	read
`send-direct-message`	write
`send-message`	write
`set-room-name`	write
`set-room-topic`	write

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: declared (5 observation(s))
Network: declared (8 observation(s))
Shell: none-observed
Dependencies: not all pinned
Secrets in source: none-found

Findings (13)

HIGHNetwork egress · net.tls_off · CWE-200, CWE-319

src/auth/tokenExchange.ts:60

agent: new https.Agent({ rejectUnauthorized: false }), // For local development with self-signed certs

Why it matters. certificate verification is disabled

Fix. leave verification on

HIGHNetwork egress · net.tls_off · CWE-200, CWE-319

src/auth/verifyAccessToken.ts:12

requestAgent: new https.Agent({ rejectUnauthorized: false }),

Why it matters. certificate verification is disabled

Fix. leave verification on

HIGHNetwork egress · net.tls_off · CWE-200, CWE-319

src/auth/verifyAccessToken.ts:45

agent: new https.Agent({ rejectUnauthorized: false }),

Why it matters. certificate verification is disabled

Fix. leave verification on

HIGHNetwork egress · net.tls_off · CWE-200, CWE-319

src/matrix/client.ts:73

const agent = new https.Agent({ rejectUnauthorized: false });

Why it matters. certificate verification is disabled

Fix. leave verification on

MEDIUMInformation disclosure · disclose.log_secret · CWE-209, CWE-532

src/auth/tokenExchange.ts:48

console.log(`Performing token exchange with IDP at ${tokenUrl}`);