Magicsword MCP Server

magicsword-mcp

A Model Context Protocol server for MagicSword. Lets users running Claude Desktop, Cursor, or any MCP-aware client manage MagicSword conversationally — list endpoints, query alerts, triage findings, mint enrollment tokens, and preview / commit policy changes.

The server is a thin, opinionated wrapper around the /api/public/v1/* customer API exposed by the Magic Portal. It runs on the user's machine, holds an msk_… API key, and speaks MCP over stdio.

Plan gate. The customer API is Enterprise-only. With a pilot-tier key the server returns a clear "this MagicSword org needs the Enterprise plan to use MCP" message; nothing else works until the org is upgraded.

Quick start

Requires Node.js 22+, an installed MCP client, and a MagicSword Enterprise API key from Magic Portal → Settings → API Keys.

Recommended: install and connect your client in one command. Setup prompts for your key privately and lets you choose Claude Desktop, Codex, Claude Code, or Cursor:

npm install -g @magicsword-io/magicsword-mcp && magicsword-mcp configure

Already know your client? Run the matching one-liner:

Prefer your client's own registration command? After saving your key locally, these also work without a global server install:

codex mcp add magicsword --env MAGICSWORD_BASE_URL=https://www.magicsword.io -- npx -y @magicsword-io/magicsword-mcp
claude mcp add --scope user --transport stdio magicsword --env MAGICSWORD_BASE_URL=https://www.magicsword.io -- npx -y @magicsword-io/magicsword-mcp

These are also a fallback when automatic registration cannot launch a client's CLI on Windows. Desktop launch still requires Node/npx to be available to that client; the recommended setup uses absolute paths instead.

Install buttons: Cursor and VS Code

First save your API key locally (once per machine):

npm install -g @magicsword-io/magicsword-mcp && magicsword-mcp configure --client manual

Then click your client's button and approve its installation prompt:

These buttons register a local npx server pointing at production. They contain no API key; the server reads ~/.magicsword/mcp.json. They require npx on the client's PATH. If a desktop app cannot find Node or npx, use the recommended setup above for absolute launch paths, or copy the absolute command and args printed by configure --client manual into its configuration.

Manual JSON fallback

After saving your key above, merge this entry into Claude Desktop's claude_desktop_config.json or Cursor's ~/.cursor/mcp.json, preserving your other servers:

{
  "mcpServers": {
    "magicsword": {
      "command": "npx",
      "args": [
        "-y",
        "@magicsword-io/magicsword-mcp"
      ],
      "env": {
        "MAGICSWORD_BASE_URL": "https://www.magicsword.io"
      }
    }
  }
}

For VS Code / Insiders, run MCP: Open User Configuration and merge this configuration (VS Code uses servers, not mcpServers):

{
  "servers": {
    "magicsword": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "@magicsword-io/magicsword-mcp"
      ],
      "env": {
        "MAGICSWORD_BASE_URL": "https://www.magicsword.io"
      }
    }
  }
}

Restart your client or start a new session, then ask it to call whoami and list_endpoints. Both must succeed to verify authentication and read access.

The official MCP Registry identifier is io.github.magicsword-io/magicsword-mcp. Client-specific details follow below.

Configure

magicsword-mcp configure

Setup asks for an API key with hidden input (mint one in Magic Portal → Settings → API Keys) and which client to connect: Claude Desktop, Codex, Claude Code, Cursor, or manual configuration. It saves the key only in ~/.magicsword/mcp.json (mode 600). The Portal defaults to https://www.magicsword.io, replacing any saved preview origin. A custom origin requires an explicit --base-url option.

Setup registers the selected client at its standard user-level location, preserves other servers and settings, and creates a private backup of existing client configuration. It updates an existing magicsword entry for JSON clients and Codex. Claude Code requires that name to be available; use its own MCP commands to remove an old registration before retrying. Codex and Claude Code registration require their respective CLIs to be installed.

To choose a client directly, or reuse a saved key without prompting:

magicsword-mcp configure --client codex
magicsword-mcp configure --non-interactive --client claude-desktop
magicsword-mcp configure --client cursor --client-config /path/to/mcp.json

The launch entry uses absolute Node and installed server paths so desktop apps can start it without inheriting your terminal's PATH. Re-run setup if you move your Node installation or install the package under a different Node version. Manual setup prints a credential-free launch entry for other local stdio MCP clients. Unattended setup without --client writes only the MagicSword file.

Restart the selected client or start a new session to load magicsword and its 21 tools. Ask it to call whoami and then list_endpoints to verify access; discovery alone does not verify API-key scopes. Claude Desktop logs are at ~/Library/Logs/Claude/mcp*.log on macOS. Browser-only clients require a remote MCP transport; this package provides a local stdio server.

If you need a per-client override instead of ~/.magicsword/mcp.json, set MAGICSWORD_API_KEY and optionally MAGICSWORD_BASE_URL in that MCP host's environment. Keep API keys out of shared config snippets and screenshots.

Tools

Write tools require matching Customer API scopes in Magic Portal, such as alerts:write, policies:write, endpoints:write, or intel:write. Event review uses alerts:read; turning selected events into policy rules uses policies:write.

Tools publish standard MCP safety annotations. Read-only discovery tools are marked read-only and idempotent; enforcement, deletion, policy assignment, rule changes, and agent upgrades are marked destructive so MCP clients can apply appropriate confirmation UX.

Example transcript

User:   Show me unack'd critical alerts from the last 24h.
Claude: [calls find_alerts severity=critical acknowledged=false since=...]
        → 3 critical alerts on 2 endpoints. Want me to triage the top one?

User:   Yes.
Claude: [calls triage_alert]
        → Evidence chain: cmd.exe spawned by winword.exe with -enc base64.
          MITRE T1059.001. Acknowledge with comment "office macro chain — under investigation"?

User:   Yes, and extract the IOCs from this report into our SOC feed.
Claude: [calls upsert_customer_intel_items]
        → Upserted 47 indicators into feed 8d6...

User:   Show me audited or blocked events from the last day.
Claude: [calls list_events hours=24 status=audited,blocked]
        → 31 events. Here are the file paths, publishers, and hashes.

User:   Allow the first 5 on the Workstations policy.
Claude: [calls manage_policy_rules action=add policy_name=Workstations event_ids=[...] status=allowed]
        → Created a new policy version with 5 allowed rules.

Configuration sources, in order of precedence

1. MAGICSWORD_API_KEY / MAGICSWORD_BASE_URL env vars (set by the MCP host).
2. ~/.magicsword/mcp.json (or $MAGICSWORD_CONFIG).
3. Default base URL https://www.magicsword.io.

Optional transport controls are MAGICSWORD_REQUEST_TIMEOUT_MS (default 30 seconds), MAGICSWORD_RESPONSE_MAX_BYTES (default 4 MiB), and MAGICSWORD_GET_RETRIES (default 2, maximum 3). Only idempotent GET requests are retried; write actions are never retried automatically.

Safety notes

• flip_to_enforcing is two-step. The first call returns a server preview and one-time confirmation token; you must show the preview to a human and pass the token back to commit. Tokens are short-lived and single-use.
• Fleet changes and deletion are explicit. Endpoint upgrades, policy assignments, and private-intel deletion return a no-op preview unless the approved follow-up call includes confirm=true.
• Windows WDAC policy edits should not use explicit flat file hashes. Use manage_policy_rules with event_ids when approving audit events so the Portal can derive supported path / publisher / filename rules, or use upsert_customer_intel_items for hash, AuthentiHash, page-hash, and TBS intelligence in a private feed.
• Secrets stay on the user's machine. The MCP server is a local stdio process; the API key is read from ~/.magicsword/mcp.json (mode 600) or an env var passed by the MCP host. Nothing is sent off-machine except the requests to the configured MAGICSWORD_BASE_URL.
• Remote Portal URLs must use HTTPS. Plain HTTP is accepted only for localhost development. Configured URLs cannot contain credentials, paths, query strings, or fragments.

Develop

npm install
npm run build
npm test
npm run test:package
npm run release:verify
node dist/index.js --version

Tests validate --help, --version, production-default migration, private client registration, preservation and rollback, configure validation, secret redaction, modern and legacy MCP startup, focused mutation confirmation, retry and timeout semantics, response-size bounds, malformed responses, write non-retry behavior, and npm pack contents. test:package installs a production-only tarball and checks the installed CLI and MCP tool discovery; release:verify checks all release metadata. See docs/RELEASING.md for npm and MCP Registry releases.