Run Hailyo from Claude or ChatGPT.

Ask your AI assistant to find leads, check what Hailyo knows about them, preview an email or put people into a sequence. It works through an API key you create and can revoke, and it never sends email by itself: every email still waits for your approval.

1. Create an API key.

In Hailyo, open Settings, then API keys, and choose Create key. Only workspace owners and admins can do this.

Give the key only the permissions it needs. Hailyo shows the key once, so copy it then. You can see when each key was last used and revoke it at any time; a revoked key stops working at once.

Permissions

Read leads leads:read: Leads, contacts, research cards and searches
Find and enrol leads leads:write: Start searches, research leads, put people into sequences
Read sequences sequences:read: Sequences and email previews
Read replies replies:read: Replies in your inbox
Read stats stats:read: Sending stats and revenue

Each key belongs to one workspace and can only see that workspace. It allows 60 requests a minute.

2. Connect Claude.

Hailyo is an MCP server at https://app.hailyo.com/api/mcp. Claude reads the key from a request header.

Claude Code

Run this once in your terminal:

claude mcp add --transport http hailyo https://app.hailyo.com/api/mcp \
  --header "Authorization: Bearer hly_your_key"

Claude Desktop

Add this to the app's configuration file (Settings, Developer, Edit config), then restart Claude Desktop. It needs Node.js.

{
  "mcpServers": {
    "hailyo": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-remote",
        "https://app.hailyo.com/api/mcp";,
        "--header",
        "Authorization: Bearer ${HAILYO_API_KEY}"
      ],
      "env": {
        "HAILYO_API_KEY": "hly_your_key"
      }
    }
  }
}

2. Or connect ChatGPT.

Build a custom GPT and give it Hailyo as an action. ChatGPT reads the whole API from one address.

1.In ChatGPT, create a GPT and open Configure, then Create new action.
2.Choose Import from URL and paste https://app.hailyo.com/api/v1/openapi.json
3.Under Authentication choose API key, auth type Bearer, and paste your key.
4.Save, then ask the GPT something like "find 20 independent dental clinics in Leeds".

Other tools and your own scripts.

Any MCP client that supports remote servers over HTTP with a header can use https://app.hailyo.com/api/mcp.

For code, the REST API lives at https://app.hailyo.com/api/v1, described at https://app.hailyo.com/api/v1/openapi.json. Send the key as a Bearer token.

curl https://app.hailyo.com/api/v1/whoami \
  -H "Authorization: Bearer hly_your_key"

What your assistant can do.

find_leads: Start a lead search from a plain-English description, or check a running one and read the leads it found. Uses your lead balance, like a search in the app.
research_lead: Read a lead's research card: facts about the company, each with the page it came from. Can research again on request (uses your AI budget).
preview_email: Show the first email of a sequence as one contact would get it. Nothing is sent or saved.
enrol: Put contacts or leads into a sequence. Suppressions, the block list, unusable or recently contacted addresses and per-company limits apply, and anyone skipped is listed with the reason.
list_replies: Read the replies in your inbox.
stats: Sent, delivered, opened, clicked, replied, positive replies, meetings, bounces, unsubscribes and revenue for a date range.

What it can't do.

An assistant gets the same checks you do in the app, and none of the switches that send.

It never sends email. People it enrols get drafts that wait for you in Review, unless the sequence is on Autopilot.
It can't turn Autopilot on, approve drafts or change sending settings. Only a workspace admin can, in the app.
It can't get past suppressions, unsubscribes, the block list, your AI budget or your lead balance.
It can't see another workspace. A key belongs to one workspace only.
It isn't told to follow anything written in a reply. Reply text is handed over marked as outside text, to be read, not obeyed.