KoltrixConnect Claude Code
Connect Claude Code to your Koltrix inbox.
One command adds Koltrix to Claude Code. Run /mcp, authenticate in your browser, and the assistant in your terminal can search, label and draft in your mail, the same tools as everywhere else, shown as text.
Run this in your terminal
claude mcp add --transport http koltrix https://mcp.koltrix.com/mcpAdd Koltrix with one command
The server URL is https://mcp.koltrix.com/mcp. There is no API key.
- Run the command below in your terminal.
- Inside Claude Code, run /mcp, choose koltrix and authenticate. Your browser opens Koltrix to sign in and approve.
- Ask about your mail in the session.
claude mcp add --transport http koltrix https://mcp.koltrix.com/mcpAdd --scope user to the command to make Koltrix available in every project rather than just the current one.
What Claude Code shows
Claude Code shows each tool's text result and does not draw cards. Everything else is the same: it sees only the mailboxes you can open, it reads, organises and drafts by default, and every draft has a link that opens it in Koltrix.
Because there is no card, sending, when an admin has allowed it and you have opted in, uses the text confirmation. Claude Code has to show you the recipients, subject and full message, wait for your yes, and name the recipients and subject back to Koltrix before it sends.
Working from a terminal
A terminal session is a good place to deal with mail in a gap between tasks. A few patterns that fit it:
- Ask for the inbox summary, then open the one conversation that matters.
- Have Claude Code read a customer's thread while you fix the bug they reported, then draft the reply and leave it in Drafts.
- Label and archive a batch of notifications with one sentence.
First things to ask
Triage
Find what matters before you open the inbox.
What came in overnight that needs a reply from me?
get_inbox_summaryWhich unread conversations are from real people, not newsletters?
list_threadsget_threadList the cold pitches from this week so I can skim them in one go.
list_threadsIs there anything waiting on me for more than three days?
search_mailget_thread
Organise
Tidy up in a sentence. Every change can be undone in Koltrix.
Label everything from our accountant Finance and archive the receipts.
search_mailapply_labelarchive_threadStar the five threads I most need to answer this week.
search_mailstar_threadMark the newsletter threads read.
list_threadsmark_readShow me which labels we have, then label the invoice emails from last month.
list_labelssearch_mailapply_label
If Claude Code cannot connect
- Claude Code says Koltrix needs authentication
Run /mcp, choose koltrix and authenticate again. The browser opens Koltrix to sign in and approve.
- Koltrix shows up in one project but not another
The command adds it to the current project by default. Re-run it with --scope user to make Koltrix available everywhere.
- The approval page says the redirect address is not allowed
The app tried to send you back to an address that is not https or is a local address. Update the app, or report it to its maker.
Questions about connecting Claude Code
What is the exact command to connect Claude Code to Koltrix?
claude mcp add --transport http koltrix https://mcp.koltrix.com/mcp. Then run /mcp inside Claude Code, choose koltrix and authenticate in your browser.
How do I make Koltrix available in every project?
Add --scope user to the command. Without it, Koltrix is added to the current project only.
Does Claude Code show interactive cards?
No. Anthropic documents card support for Claude on the web, in Claude Desktop and on mobile, while Claude Code shows the text result of each tool.
Can Claude Code send email?
Only when an admin allows assistant sending and you opt in when you connect, and then only after it shows you the whole message and you say yes. At most 10 recipients a message, with no Bcc and no attachments.
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.
- 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.
- Every tool in the Koltrix MCP server, explainedA tour of the reading, organizing, drafting and sending tools: inputs, permissions, what each returns, and what is missing on purpose, like delete and forward.
- MCP, OAuth and permissions explained for your emailWhat the Approve button grants: OAuth sign-in with no password or key, four separate permissions, token lifetimes, instant revocation, and a checklist to reuse.
Also in this guide
- CursorOne entry in mcp.json, then sign in.
- 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.