Connect MissingLinkz to Cursor via MCP: 5-Minute Setup Guide

What you need before starting

Cursor 0.42 or later

MCP support in Cursor shipped in early 2025. Open Cursor, go to Help › About, and confirm the version. Update if needed.

Node.js 18+

The MissingLinkz CLI is an npm package. Check with node --version. If you're using Cursor, Node is almost certainly already installed on your machine.

MissingLinkz CLI installed globally

Run npm install -g missinglinkz if you haven't already. Confirm it's available: mlz --version.

Step 1 — Install the CLI and get an API key

If you don't have MissingLinkz installed yet, install it globally and register for a free account:

Registration generates an API key (mlz_live_…) that you'll set as the MLZ_API_KEY environment variable. The key is required for campaign link storage and the full MCP tool set.

Step 2 — Create .cursor/mcp.json

Cursor reads MCP server configuration from a file at .cursor/mcp.json in your project root (project-scoped) or at ~/.cursor/mcp.json (global, applies to all projects). Use the global location if you want MissingLinkz available everywhere.

Create or open the file and add the MissingLinkz server entry:

{
  "mcpServers": {
    "missinglinkz": {
      "command": "mlz",
      "args": ["mcp"],
      "env": {
        "MLZ_API_KEY": "mlz_live_your_key_here"
      }
    }
  }
}

Replace mlz_live_your_key_here with your actual key from mlz auth status. The env block is the recommended way to pass the API key — it keeps the key out of shell history and is visible only to the MCP server process that Cursor spawns.

If you already have other MCP servers configured, add the missinglinkz entry alongside them inside the existing mcpServers object — do not create a second mcpServers key.

Step 3 — Verify the connection in Cursor

Reload Cursor after saving the config file. To confirm the MCP server is connected:

1. Open the Cursor command palette (Cmd+Shift+P on macOS, Ctrl+Shift+P on Windows/Linux)
2. Search for MCP: List Servers or open Settings › Features › MCP Servers
3. You should see missinglinkz listed with status connected

If the server shows as disconnected, verify that mlz is on your system PATH and that the API key is correctly pasted without extra whitespace. Run mlz auth status in your terminal to confirm the key is valid.

You can also verify by running mlz mcp directly in a terminal — the command will appear to hang, which is the server waiting for JSON-RPC input over stdin. That's the expected behavior. Press Ctrl+C to exit. If it starts without error, the binary is working correctly.

Example prompts in the Cursor AI composer

Once connected, type these prompts in the Cursor composer to trigger MissingLinkz tool calls. The agent will call the appropriate tool, show the JSON result, and interpret it for you.

Prompt 1: validate a campaign link before publishing

You: Validate this campaign link before I share it on LinkedIn:
https://example.com/landing?utm_source=linkedin&utm_medium=social&utm_campaign=q2-launch
Check SSL, OG tags, and whether the redirect preserves UTM params.

Cursor (calls mlz_preflight):
The link is ready to publish. All 12 checks passed:
- SSL: HTTPS confirmed
- Resolution: 200 OK in 241ms
- Redirects: No hops, UTM params preserved
- OG tags: title, description, og:image all present
- Twitter Card: summary_large_image configured

Prompt 2: build a tracked UTM link

You: Build a UTM-tracked link for our Q2 LinkedIn campaign.
Destination: https://example.com/product-launch
Source: linkedin, Medium: social, Campaign: q2-product-2026

Cursor (calls mlz_build_link):
Here's your tracked URL:
https://example.com/product-launch?utm_source=linkedin&utm_medium=social&utm_campaign=q2-product-2026
Link ID: lnk_9wlvd9qi · Campaign: cmp_kbcht77d

Prompt 3: inspect a landing page's social sharing readiness

You: Inspect https://example.com/new-landing for OG tags and
Twitter Card. Tell me if anything is missing before we run ads
pointing to it.

Cursor (calls mlz_inspect_destination):
Found 2 issues:
- WARN: og:image is missing. LinkedIn and X will show no preview image.
- PASS: og:title and og:description are present.
- PASS: Twitter Card (summary_large_image) is configured.
Recommendation: Add an og:image tag before running any paid campaigns
pointing to this page.

Full list of available MCP tools

When Cursor is connected to the MissingLinkz MCP server, it can call any of these tools. The agent selects the right tool based on what you ask for.

For the full command reference including all flags and JSON response shapes, see the MCP Marketing Tools guide and the SKILL.md.

Tips for using MissingLinkz in the Cursor agent

Be specific about the campaign parameters

The agent will infer parameters from context when possible, but providing explicit values (source: linkedin, medium: social, campaign: q2-launch) avoids unnecessary clarification turns and produces more accurate UTM link outputs.

Ask for the full preflight report for new landing pages

mlz_preflight is the right tool when a landing page is new or recently updated — it checks both the URL resolution and the OG tags in one call. Use mlz_validate_url for a faster check on pages you've already inspected and know have working OG tags.

Use mlz_suggest_naming when you're unsure of conventions

If your team has existing campaigns with specific naming patterns (e.g., utm_medium=paid-social vs paid_social vs social), ask the agent to run mlz_suggest_naming before building a new link. It will surface your historical convention and apply it consistently.

The MCP server uses stdio transport only

Unlike HTTP-based MCP servers, mlz mcp communicates over stdin/stdout. Cursor manages the process lifecycle — you don't need to start the server manually. If you see "transport error" messages, it usually means mlz is not on PATH. Run which mlz and check that the result is a valid path.

FAQ

Does MissingLinkz work with the Cursor Agent or just the chat?

Both. MCP tools are available in any Cursor context where the agent can make tool calls — this includes the AI Chat panel (Cmd+L), the Composer (Cmd+K), and Cursor Agent mode. The agent automatically chooses the right tool based on your prompt.

Do I need to restart Cursor after editing .cursor/mcp.json?

Yes. Cursor reads the MCP config at startup. After any change to the config file — including updating the API key or adding new servers — reload Cursor to pick up the changes. Use File › Quit and reopen, not just a window close/open cycle, to ensure a full process restart.

Can I use a .env file for the API key instead of hardcoding it in mcp.json?

The env block in .cursor/mcp.json sets environment variables for the MCP server process specifically. You can omit the env block entirely if MLZ_API_KEY is already exported in your shell environment — Cursor will inherit it. The CLI also reads from a config file at ~/.missinglinkz/config.json written by mlz auth login, which means you may not need to pass the key explicitly at all if you've logged in via the CLI.

What if I want the MCP connection to apply to all my Cursor projects?

Create or edit ~/.cursor/mcp.json in your home directory instead of the project-scoped .cursor/mcp.json. Entries in the global file apply to every project you open in Cursor, so you only need to configure the API key once.

Using Claude Code instead of Cursor?

The setup is nearly identical. See How to Use MissingLinkz with Claude Code — it covers the same MCP config pattern for Claude Desktop and Claude Code.

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