KoltrixConnect Cursor
Connect Cursor to your Koltrix inbox.
Add Koltrix to Cursor's mcp.json with one URL, sign in when Cursor asks, and your editor's assistant can look up the customer email behind a bug, summarise a thread or leave a draft reply, without leaving the code.
Add this to mcp.json
{
"mcpServers": {
"koltrix": {
"url": "https://mcp.koltrix.com/mcp"
}
}
}Add Koltrix to mcp.json
The server URL is https://mcp.koltrix.com/mcp. There is no API key.
- Add Koltrix to ~/.cursor/mcp.json to have it in every project, or to .cursor/mcp.json inside one project.
- Open Cursor's MCP settings, find Koltrix and sign in when Cursor asks. Cursor sends you to Koltrix to approve.
{
"mcpServers": {
"koltrix": {
"url": "https://mcp.koltrix.com/mcp"
}
}
}Any MCP client that supports remote servers over Streamable HTTP with OAuth can use the same URL. For a client that can only start local (stdio) servers, the docs show how to bridge to Koltrix with mcp-remote.
User file or project file
The two files do different jobs. ~/.cursor/mcp.json is yours alone and applies to every project you open. .cursor/mcp.json lives in a repository and applies to that project; if you commit it, teammates get the entry too, and each of them signs in with their own Koltrix account.
The file holds only the URL. There is no secret in it, which is why it is safe to commit: the sign-in happens in your browser and the access is tied to you.
- Everyone who connects sees only the mailboxes they can open in Koltrix.
- A teammate who cannot open the support mailbox in Koltrix will not see it through Cursor either.
What it is good for in an editor
Developers keep customer context in email: the bug report with the exact error, the integration question, the invoice for a tool. Asking Cursor about it keeps you in the editor.
- Find the thread where a customer reported the checkout bug and quote the error they pasted.
- Summarise what the vendor asked for in their last three emails, then draft a reply.
- List unread mail from your payment provider and label it Finance.
Results come as text
We have not been able to confirm whether Cursor draws interactive cards, so do not expect them. The tools return text results that the assistant reads and summarises, with a link that opens each conversation or draft in Koltrix.
Sending, when allowed, works the text way: the assistant shows the draft, you say yes, and it confirms the recipients and subject before Koltrix sends. See the security page for the exact steps and limits.
If Cursor cannot connect
- Koltrix shows as disconnected or needs sign-in
Open Cursor's MCP settings, find Koltrix and sign in again. A connection that was revoked or unused for 30 days has to be reconnected.
- The server does not appear
Check the JSON is valid and that the entry sits under mcpServers, then reload Cursor's MCP settings.
- Connecting from a work network fails
The network must let Cursor reach mcp.koltrix.com and your browser reach app.koltrix.com.
Questions about connecting Cursor
Is it safe to commit .cursor/mcp.json?
Yes. The file contains only the server URL, no key or token. Each person signs in with their own Koltrix account, and each connection can be revoked on its own.
Does Cursor show interactive cards for Koltrix?
We cannot confirm that it does, so assume text. Koltrix offers cards only to an app that says it supports them, and otherwise sends the same tools with text results.
Can Cursor send email from my Koltrix inbox?
By default it reads, organises and drafts. If an admin allows assistant sending and you opt in, Cursor has to show you the message and get your yes before it sends, within the limits of 10 recipients, 20 sends a day per connection and 50 per workspace.
Can I use the same URL in other editors?
Yes, in any app that supports remote MCP servers over Streamable HTTP with OAuth sign-in. The setup guide in the docs covers other apps.
Go deeper
Guides from the blog
- Connect Cursor and Claude Code to Koltrix: setup and safetyAdd Koltrix to Cursor with a three-line config or to Claude Code with one command, then use your inbox beside your code, with a safety habit for coding agents.
- What is MCP? A plain-English guide for email usersMCP, the Model Context Protocol, explained for people who live in email: clients and servers, how connections work, and what an email server should expose.
- MCP, the email API or Zapier: which one fits which email job?MCP assistants, an email API and automation tools solve different problems. See which fits triage, product email and routine rules, and how to combine them.
- Troubleshooting a Koltrix MCP connection: symptoms and fixesNot authorized, missing permissions, no send tool, a wrong workspace or no card: a symptom-first checklist for fixing a Koltrix connection in minutes.
Also in this guide
- Claude CodeOne command in your terminal, then /mcp.
- ClaudeAdd Koltrix to Claude as a custom connector.
- ChatGPTCreate a custom connector with OAuth in ChatGPT.
- Tools referenceEvery tool, its permission, inputs and an example.
Related on koltrix.com
Try it on your own mail.
Add your domain, connect your assistant and ask what needs a reply. Every plan starts with a free trial, no card.