MCP server for Grok

Cold email MCP server for Grok

Connect Grok to the Outreach2day MCP server as a custom connector on grok.com, from Grok Build, or through the xAI API. Grok quotes domains and mailboxes when you turn on Prepare orders at sign-in, runs warmup, launches campaigns and reads replies. You approve and pay every order on Stripe.

https://public.outreach2day.com/mcp
Open Grok connectors

Copies the server URL and opens Grok Connectors

Setup guide
  1. Choose New Connector → Custom
  2. Name it Outreach2day and paste the server URL
  3. Click Connect and sign in with your Outreach2day account
  • Orders paid through Stripe after you approve them
  • $2.50 per mailbox a month
xAI API · Outreach2day MCP

Which of our mailboxes are ready to send, and which ones are dragging the inbox rate down?

called outreach2day tools

38 of 40 mailboxes are warm. Inbox rate 94% over 7 days.

Low: sam@getacme.info (71%) and lee@acmehq.com (68%).

Both send in the Q4 campaign. Want the per-step stats before you decide?

teams have used Outreach2day
3,600+
emails sent a day
40M+

Among them

Can Grok run cold email through MCP?

Yes. On grok.com, add the server as a custom connector and sign in to Outreach2day. In Grok Build, add it with grok mcp add and sign in from /mcps. The xAI API takes it as a remote MCP tool with an API key in the authorization field. Grok then checks domains, quotes mailboxes (with Prepare orders turned on at sign-in), runs warmup, launches campaigns and reads replies while you pay each order on Stripe.

Cold email in Grok, step by step

  1. 1

    Add the connector

    Add the server URL as a custom connector on grok.com and sign in, or pass it to the xAI API as a remote MCP tool with your key in a header

  2. 2

    Quote and pay

    Grok asks for a quote and shows it to you. You approve it and pay on the Stripe page Grok links

  3. 3

    Warm up and launch

    Grok tracks setup and starts warmup. After 14 days of warmup and a passed preflight, ask Grok to launch

  4. 4

    Watch the numbers

    Ask Grok for replies and per-mailbox inbox rate. It flags weak mailboxes and pauses the campaign when you say so

Outreach2day in Grok: where to connect

Setup details

Grok: files, sign-in and limits

What Grok's own documentation says about connecting a remote MCP server.

Grok Build CLI
Add the server by URL. Grok Build finds the Outreach2day sign-in on its own and keeps the token in ~/.grok/mcp_credentials.json. The entry goes to ~/.grok/config.toml, or .grok/config.toml with --scope project. xAI docs: Grok Build MCP servers
Grok Build CLI
grok mcp add --transport http outreach2day https://public.outreach2day.com/mcp# then, in a grok session: /mcps, select outreach2day, press i to sign in
Grok Build, headless
For grok -p and CI, send a key header. ${VAR} expands in the url and headers, so single quotes keep the key out of the file. grok mcp doctor checks the connection. xAI docs: Grok Build MCP servers
Grok Build, headless
grok mcp add --transport http outreach2day https://public.outreach2day.com/mcp \  --header 'Authorization: Bearer ${OUTREACH2DAY_API_KEY}'
Servers you already have
Grok Build also reads servers configured in ~/.claude.json, .cursor/mcp.json and .mcp.json. xAI docs: Grok Build MCP servers
grok.com
Connectors, New Connector, Custom, paste the server URL and sign in. Custom connectors are available to all Grok users; the server has to be reachable from the public internet. xAI docs: Grok connectors
Grok Business and Enterprise
An admin with Team Read-Write adds the connector first: console.x.ai, Grok Business, Connectors, Add Connector, Other. xAI docs: connector management
xAI API
An mcp tool with server_url, server_label, server_description, allowed_tools and authorization. xAI sends authorization as the whole Authorization header, so write it as Bearer and the key. require_approval is not supported, so the server's own guardrails apply: purchases stop at a Stripe link. xAI docs: remote MCP tools
xAI API
curl https://api.x.ai/v1/responses \  -H "Authorization: Bearer $XAI_API_KEY" \  -H "Content-Type: application/json" \  -d '{    "model": "grok-4.7",    "input": "Which of my mailboxes are ready to send?",    "tools": [{      "type": "mcp",      "server_label": "outreach2day",      "server_description": "Cold email domains, mailboxes, warmup, campaigns and replies",      "server_url": "https://public.outreach2day.com/mcp",      "authorization": "Bearer '"$OUTREACH2DAY_API_KEY"'"    }]  }'

Works with Outreach2day

  • grok.com custom connector with OAuth sign-in
  • Grok Build CLI with OAuth sign-in, or a header from $OUTREACH2DAY_API_KEY for headless runs
  • The xAI API with Bearer and your key in the authorization field

Does not work

  • require_approval in the xAI API
  • A local server with your key exposed through a tunnel for grok.com: use the hosted server

The tools Grok gets and the guardrails on orders are the same in every client: tool list, what the agent can and cannot do.

Prompts

Things to ask Grok

Plain language is enough. The agent picks the tools and asks before anything costs money.

  • Check if these domains are free: tryacme.com, getacme.info, acmehq.com.
  • Quote 4 domains and 16 mailboxes for acme.com and send me the payment link.
  • Which mailboxes are dragging the inbox rate down this week?
  • Is the Q4 campaign ready to launch? Run the preflight check.
  • List today's positive replies with the lead's company and the step that got the reply.
  • Compare inbox rate by domain for the last 7 days and flag any domain below 85%.

What Grok can do with the server, job by job

Each page lists the tools for the job, an example session, prompts per assistant and the limits.

Setup

Connect Grok

Add https://public.outreach2day.com/mcp to Grok and sign in with your Outreach2day account when it asks. Then ask: "Check my Outreach2day account status". An API key is only for CI and headless setups.

Setup steps

OAuth sign-in

grok.com (custom connector)

  1. Open grok.com/connectors, click New Connector, then Custom
  2. Name it Outreach2day, paste https://public.outreach2day.com/mcp as the Server URL and add it
  3. Grok opens the sign-in in a pop-up window. If the browser blocks it, allow pop-ups for grok.com and click Connect again
  4. The first time the client connects, it opens an Outreach2day sign-in page in your browser. Sign in, turn on Prepare orders so the assistant can quote orders and create Stripe checkout links, and allow access
  5. On Grok Business or Enterprise, an admin adds the connector first in console.x.ai: Grok Business, Connectors, Add Connector, Other
xAI docs: Grok connectors
OAuth sign-in

Grok Build CLI

  1. Add the server with the command below. It goes to ~/.grok/config.toml
  2. Start grok, open /mcps, select outreach2day and press i. Grok Build also opens the sign-in on first use
  3. The first time the client connects, it opens an Outreach2day sign-in page in your browser. Sign in, turn on Prepare orders so the assistant can quote orders and create Stripe checkout links, and allow access
  4. For headless runs (grok -p, CI), add the server with a key header instead, shown under Setup details
xAI docs: Grok Build MCP servers
Terminal
grok mcp add --transport http outreach2day https://public.outreach2day.com/mcp# then, in a grok session: /mcps, select outreach2day, press i to sign in
API key

xAI API

  1. Create an API key in the Outreach2day app (API keys, New key) and export it as OUTREACH2DAY_API_KEY
  2. Add Outreach2day to tools as an mcp tool. xAI puts the authorization value into the Authorization header as written, so keep the Bearer prefix
  3. Use allowed_tools to limit which tools Grok can call
xAI docs: remote MCP tools
curl · xAI Responses API
curl https://api.x.ai/v1/responses \  -H "Authorization: Bearer $XAI_API_KEY" \  -H "Content-Type: application/json" \  -d '{    "model": "grok-4.7",    "input": "Which of my mailboxes are ready to send?",    "tools": [{      "type": "mcp",      "server_label": "outreach2day",      "server_description": "Cold email domains, mailboxes, warmup, campaigns and replies",      "server_url": "https://public.outreach2day.com/mcp",      "authorization": "Bearer '"$OUTREACH2DAY_API_KEY"'"    }]  }'

Book a call

Book a 30-minute call

Talk to the team that runs the MCP server. We check your setup for Grok and your first order.

  • Free 30-minute call
  • Size domains and mailboxes for your volume
  • Walk through a quote and the Stripe checkout
  • Check your Grok setup

See open times in your time zone and book on this page.

Or open the booking page

Customers

Teams that send with Outreach2day

  • “That was the best infrastructure and value for money I saw.”
    Ido RebhunIdo RebhunRenaissance
  • “…deliverability with your inboxes is better than our outlook/google inboxes…”
    Daniel DultsinDaniel DultsinControl
  • “We really would like to thank you for that report. We don’t know what we are doing with email and it is very reassuring to us to know we have a partner on top of the ball.”
    ReilcapBill OConnorReilcap

Questions

Or talk to the team

Does Grok support MCP servers?

Yes, in three places: Grok Build (the CLI), custom connectors on grok.com, and the xAI API, which takes remote MCP servers as tools.

Can I connect the Outreach2day MCP server in the Grok app?

Yes. grok.com custom connectors take a remote MCP server URL; Grok opens the Outreach2day sign-in page and you allow access.

Can I limit which Outreach2day tools Grok can call?

In the xAI API, pass allowed_tools. Give a reporting agent only the read tools. The API has no approval step, so our server's own rules apply: no card is charged by a tool. On grok.com, open the connector and turn tools off one by one.

Does Grok Build pick up servers I set up for Claude Code or Cursor?

Yes. It reads ~/.claude.json, .cursor/mcp.json and .mcp.json, so a server you already added there shows up in Grok Build too.

Other AI clients

The same server and the same tools in every client. Only the setup differs.

Guides for MCP and the API

Run cold email from Grok

Domains, mailboxes, warmup, campaigns and replies from Grok. You approve every order.

Setup stepsGet API key