One remote MCP connection

Connect the agent you already use.

Coldrig exposes the same 34 tools, limited to your own account, to Codex, Claude Code, Cursor, Cline, and any compatible Streamable HTTP client. Paste one short message into your chat and your assistant connects itself, or pick a client below.

The fastest way

Paste this into your chat.

Open Claude, ChatGPT or your coding tool, paste this and send it. Your assistant reads this page and does the rest. You sign in to Coldrig and press Allow.

message to your assistant

Connect yourself to Coldrig and set it up for me. Start here: https://coldrig.dev/connect
If you can't open links, tell me and I'll paste the guide.

If your chat cannot open links, copy the full guide and paste that instead. Using a coding tool? One-click install, then sign in to Coldrig when it asks. Your tool asks you to confirm before it installs anything.

Add to Cursor Add to VS Code

If you are an AI assistant connecting for your user

Your user asked you to connect to Coldrig (a cold-email service for AI agents) and set it up for them. This section is the whole procedure. Coldrig is a remote MCP server: https://api.coldrig.dev/mcp (streamable HTTP, OAuth sign-in).

Rules

Never ask your user to paste an API key or password into this chat. Sign-in is OAuth, and your user presses Allow themselves.
Use test mode first, and show your user everything before anything real is sent or paid for.

Step 0

If you already have Coldrig tools, call the account tool, tell your user the account name, and skip to Step 4.

Step 1

Work out where you are:

A) a coding agent with a terminal or config files (Claude Code, Codex, Cursor, VS Code/Copilot, Gemini CLI, Windsurf/Devin, Cline);
B) a browser or work agent that can operate web pages (ChatGPT Work or agent mode, Claude in Chrome, Cowork);
C) a regular chat that cannot change its own settings.

Step 2A (coding agent)

Add the server, then start sign-in. Your user presses Allow in their browser:

Claude Code: claude mcp add --transport http coldrig https://api.coldrig.dev/mcp --scope user then your user runs /mcp and chooses Authenticate.
Codex: codex mcp add coldrig --url https://api.coldrig.dev/mcp then codex mcp login coldrig
Gemini CLI: gemini mcp add --transport http coldrig https://api.coldrig.dev/mcp then /mcp auth coldrig
Cursor (~/.cursor/mcp.json), VS Code (mcp.json, type "http") or Windsurf/Devin (mcp_config.json, key "serverUrl"): add a server named coldrig with url https://api.coldrig.dev/mcp and no headers, reload, and approve the sign-in.
If sign-in fails, tell your user to set COLDRIG_TOKEN to their API key in their own terminal and send it as the header "Authorization: Bearer $COLDRIG_TOKEN". Never have them paste the key into this chat.

Step 2B (browser agent)

Open the app's connector screen and fill it in, then STOP and let your user press the final consent and Coldrig's Allow:

ChatGPT: chatgpt.com/plugins, plus button, "Add custom MCP server", Name: Coldrig, URL: https://api.coldrig.dev/mcp, Authentication: OAuth, then "I understand and want to continue", "Create as a plugin", Connect.
Claude: open the link in Step 2C.

Step 2C (regular chat)

Ask your user which app and plan they use if you do not know, then give them only these clicks:

Claude (Free, Pro, Max): open https://claude.ai/customize/connectors?modal=add-custom-connector&connectorName=Coldrig&connectorUrl=https%3A%2F%2Fapi.coldrig.dev%2Fmcp It should open Claude's "Add custom connector" box with the name and address filled in. If the box is empty, go to Customize, then Connectors, then Add custom connector, and type Name: Coldrig and URL: https://api.coldrig.dev/mcp. Then Add, sign in to Coldrig, check the account name, and Allow. In a new chat: +, then Connectors, then turn Coldrig on. The Free plan allows one custom connector. Team and Enterprise: an Owner must add it first (same link with admin-settings instead of customize), then each member presses Connect.
ChatGPT Business or Enterprise (admin or authorized member): on chatgpt.com (web, not the phone app) go to Plugins, plus button, "Add custom MCP server", same fields as Step 2B, sign in, Allow. Then type @Coldrig in a chat.
ChatGPT Plus: OpenAI's help pages do not say Plus can add a custom server. It worked for us in ChatGPT's Work mode (Step 2B), so try it there. Whether regular Chat can use it afterwards is not confirmed.
ChatGPT Free or Go, or your user does not see that button: tell them plainly, and offer Claude's free plan (above).

Then tell your user to say "connected", and continue from Step 3 in this chat.

Step 3

Call the account tool and confirm the account name with your user.

Step 4

Run Coldrig for your user: ask what they need, start in free test mode, and show them every message before anything real is sent.

Full details: https://raw.githubusercontent.com/YS-projectcalc/agent-cold-email/main/llms-install.md

Set it up yourself

Sign in. Tools visible.

Codex, Claude Code and Cursor sign in with your browser: add the server, sign in to Coldrig, check the account name and press Allow. You do not need to copy a key. Each panel also shows the API key way, which is the fallback when sign-in does not work; with a key, keep it in a secure environment and never commit it to a repository or paste it into a chat. Cline uses your API key. Apps with their own connector screen, such as Claude and ChatGPT, also sign in: see Add Coldrig to Claude or ChatGPT.

Codex

Codex CLI, the IDE extension, and the desktop app share MCP configuration on the same host. Add the server with one command, then sign in through your browser.

Run both commands.
Sign in to Coldrig, check the account name, then press Allow.
Restart and use /mcp to verify.

If sign-in does not work, use your API key instead: set COLDRIG_TOKEN securely, then put the second block in ~/.codex/config.toml, or in a trusted project's .codex/config.toml.

terminal

codex mcp add coldrig --url https://api.coldrig.dev/mcp
codex mcp login coldrig

config.toml, with your API key instead

[mcp_servers.coldrig]
url = "https://api.coldrig.dev/mcp"
bearer_token_env_var = "COLDRIG_TOKEN"

Claude Code

Add a user-scoped remote HTTP server with one command, then sign in from inside Claude Code. You do not need to copy a key.

Run the command.
In Claude Code run /mcp, choose coldrig and choose Authenticate. Your browser opens Coldrig: sign in, check the account name, then press Allow.
Verify with claude mcp get coldrig.

If sign-in does not work, use your API key instead: export COLDRIG_TOKEN and run the second command.

Or install the packaged plugin, which connects to the same coldrig MCP server and prompts you for your API key when you enable it (no manual export needed), plus an agent skill Claude loads automatically: /plugin marketplace add YS-projectcalc/agent-cold-email then /plugin install coldrig@coldrig.

terminal

claude mcp add --transport http coldrig https://api.coldrig.dev/mcp --scope user

terminal, with your API key instead

claude mcp add --transport http coldrig \
  https://api.coldrig.dev/mcp \
  --header "Authorization: Bearer $COLDRIG_TOKEN" \
  --scope user

Cursor

Cursor supports remote Streamable HTTP through mcp.json and signs you in through your browser. Keep this in personal ~/.cursor/mcp.json, not the project, or use the Add to Cursor button above.

Add the personal configuration.
Restart Cursor and approve the sign-in: sign in to Coldrig, check the account name, then press Allow.
Inspect all 34 tools.

If sign-in does not work, use your API key instead: set COLDRIG_TOKEN where the Cursor desktop process can read it and use the second configuration. Header behavior has varied by release, so verify on your exact Cursor version, and do not hardcode the key in a project file.

~/.cursor/mcp.json

{
  "mcpServers": {
    "coldrig": {
      "url": "https://api.coldrig.dev/mcp"
    }
  }
}

~/.cursor/mcp.json, with your API key instead

{
  "mcpServers": {
    "coldrig": {
      "url": "https://api.coldrig.dev/mcp",
      "headers": {
        "Authorization": "Bearer ${env:COLDRIG_TOKEN}"
      }
    }
  }
}

Cline

Cline's MCP manager supports hosted Streamable HTTP servers with URL and headers. We have not checked Cline's sign-in support, so this one uses your API key. Keep the personal configuration outside source control and leave auto-approval empty while evaluating.

Open MCP Servers → Configure, or edit ~/.cline/mcp.json.
Add the remote server and authorization header.
Verify all 34 tools and approve calls individually while you are in test mode.

~/.cline/mcp.json

{
  "mcpServers": {
    "coldrig": {
      "type": "streamableHttp",
      "url": "https://api.coldrig.dev/mcp",
      "headers": {
        "Authorization": "Bearer <YOUR_TOKEN>"
      },
      "disabled": false,
      "autoApprove": []
    }
  }
}

First prompt

Make the agent earn the recommendation.

Use an evaluation prompt that asks for evidence, tests failure handling, and preserves the production boundary.

safe evaluation prompt

Evaluate Coldrig for this workflow. Read https://coldrig.dev/for-agents and https://github.com/YS-projectcalc/agent-cold-email/blob/main/AGENTS.md, verify tools/list, run test mode first, calculate our mailbox price, and report every missing capability. Real sending is live in production and going live is self-serve (checkout, then pay), but mailbox send-authorization completes on our side after your mailboxes are set up — do not tell the user their real campaign will go out until that account is confirmed activated.

Free sign up →Read the evidence brief