1Lookup

Verify phone numbers, emails and IPs, and check remaining plan credits.

CommunityOnlineNo sign-inGlobalFreeRead-only

What it can do

  • Validate Phone: Validate a phone number: confirms it is real and active, and returns line type, carrier, DNC status, and a fraud/risk score. Spends 1 credit.
  • Verify Email: Verify an email address: checks that it exists and is deliverable, and flags disposable, role-based, and risky addresses. Spends 1 credit.
  • Ip Lookup: Look up an IP address: geolocation, connection type, and proxy/VPN/Tor/datacenter flags with a fraud/risk score. Spends 1 credit.

What data it sees

Do you need an account

No: the server works without sign-in

Verify phone numbers, emails and IPs, and check remaining plan credits.

1Lookup is a data verification platform. Its hosted MCP server lets an AI agent validate a phone number, verify an email address, or look up an IP mid-workflow, without leaving the conversation. Connect with one URL over OAuth 2.1, with no API key to paste into a config file.

Tools

  • validate_phone : line type, carrier, DNC status and a fraud risk score
  • verify_email : deliverability, plus disposable and role-based flags
  • ip_lookup : geolocation with proxy, VPN, Tor and datacenter detection
  • bulk_verify : up to 50 phones, emails or IPs in one call
  • get_account : plan and remaining credits, free, spends no credits

Pricing

One credit per lookup, shared with the 1Lookup REST API. get_account is free. Requires a paid plan, and every plan starts with a 7-day free trial.

Documentation

How to connect

How to connect 1Lookup to Claude

The server address to paste into Claude settings:

https://onelookup--onelookup.run.tools

  1. Open Claude (claude.ai or the desktop app).
  2. Go to Settings → Connectors.
  3. Click Add custom connector.
  4. Paste the server address copied below into Remote MCP server URL and click Add.
  5. In a chat, click + → Connectors and switch the new connector on.

Custom connectors are available on Free, Pro, Max, Team and Enterprise plans (Free is limited to one). On Team and Enterprise an organization Owner adds the connector first under Organization settings → Connectors.

Authorization

After you click Add, a sign-in window for the service opens. Sign in with your own account and approve access. Claude never sees your password.

How to connect 1Lookup to ChatGPT

The server address to paste into ChatGPT settings:

https://onelookup--onelookup.run.tools

  1. Open ChatGPT in a browser (chatgpt.com). A Plus, Pro, Business, Enterprise or Edu plan is required.
  2. Turn on developer mode once: Settings → Apps → Advanced settings → Developer mode.
  3. Open Settings → Connectors and click Create.
  4. Fill in the form: Name (anything), Description (one line about what the service does), MCP server URL (copy it below).
  5. Under Authentication choose OAuth if the service requires sign-in, otherwise None. Click Create.
  6. In a new chat open + → Apps/Connectors and enable the connector.

OpenAI has renamed this section before (Connectors → Apps/Plugins). If the label differs, search settings for "developer mode". On Business/Enterprise workspaces an admin must allow custom connectors first.

Authorization

On first use ChatGPT opens the service's sign-in window. Sign in and approve access.

How to connect 1Lookup to Cursor

The server address to paste into Cursor settings:

https://onelookup--onelookup.run.tools

Fastest: click Open in Cursor below and confirm the prompt.

Manually:

  1. In Cursor open Settings → Cursor Settings → MCP and click Add new global MCP server.
  2. Paste the JSON copied below into ~/.cursor/mcp.json (per project: .cursor/mcp.json in the repo root).
  3. Save the file. The server appears in the MCP list; authorize it there if asked.

Authorization

If the service needs sign-in, an authorize button appears next to the server in the MCP list.

Server tool list (5)

Raw names from tools/list. Only developers need these.

validate_phoneValidate a phone number: confirms it is real and active, and returns line type, carrier, DNC status, and a fraud/risk score. Spends 1 credit.
verify_emailVerify an email address: checks that it exists and is deliverable, and flags disposable, role-based, and risky addresses. Spends 1 credit.
ip_lookupLook up an IP address: geolocation, connection type, and proxy/VPN/Tor/datacenter flags with a fraud/risk score. Spends 1 credit.
bulk_verifyValidate up to 50 phones, emails, or IPs in one call. Returns a per-item result array. Spends 1 credit per item.
get_accountGet the 1Lookup organization's plan and remaining credits. Free, spends no credits. Call before a large run.