GTM and Outreach
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From an API key to a running campaign.

Four requests: connect a mailbox, import contacts, create a campaign, then check, test and launch. Create your key in Settings, then API & MCP.

Before you start. Every request needs Authorization: Bearer gtm_.... Replace api.yourdomain.com with your API address. Times are ISO 8601 in UTC.
// A tiny helper used in the JavaScript examples
const BASE = "https://api.yourdomain.com/v1";
async function api(method, path, body) {
  const res = await fetch(BASE + path, {
    method,
    headers: { Authorization: "Bearer " + process.env.GTM_KEY, "content-type": "application/json" },
    body: body ? JSON.stringify(body) : undefined,
  });
  const data = await res.json();
  if (!res.ok) throw new Error(data.error); // errors are plain sentences
  return data;
}

  1. Connect a mailbox

    Use an app password for Google Workspace or Zoho, or any SMTP/IMAP server. We test the login before saving. New mailboxes start with a slow start; add "slowStart": false if it's already warmed up.

    API=https://api.yourdomain.com/v1
KEY="Authorization: Bearer gtm_..."

curl -X POST $API/mailboxes/smtp -H "$KEY" -H 'content-type: application/json' \
  -d '{"email":"[email protected]","name":"Sam","password":"app-password","provider":"google"}'

  2. Import contacts

    Send rows directly, or a Google Sheets link. Every address is checked. The response tells you how many were imported and what was left out.

    curl -X POST $API/contacts/import -H "$KEY" -H 'content-type: application/json' \
  -d '{"listName":"SaaS founders","rows":[
        {"email":"[email protected]","first_name":"Ana","company":"Startup"},
        {"email":"[email protected]","first_name":"Raj","company":"Fintech"}]}'

# {"listId":"...","imported":2,"verification":{"valid":2,"role":0,"disposable":0,"no_mail_server":0}, ...}

  3. Create the campaign

    A campaign starts as a draft. Steps with an empty subject go out as replies in the same thread.

    curl -X POST $API/campaigns -H "$KEY" -H 'content-type: application/json' -d '{
  "name": "Founders Q4", "listIds": ["LIST_ID"], "mailboxIds": ["MAILBOX_ID"], "dailyLimit": 30,
  "window": {"start":"10:00","end":"17:00","tz":"Asia/Kolkata","days":["Mon","Tue","Wed","Thu","Fri"]},
  "steps": [
    {"waitDays":0,"subject":"{Quick|Short} question, {{first_name|there}}","body":"Hi {{first_name|there}},\n\n...","format":"plain"},
    {"waitDays":3,"subject":"","body":"Bumping this up, {{first_name|there}}.","format":"plain"}
  ]}'

  4. Check, test, then launch

    The check lists anything that would block the launch. Send yourself every step as a test, then launch. An account's first campaign gets a short content review before it starts.

    curl $API/campaigns/CAMPAIGN_ID/check -H "$KEY"

curl -X POST $API/campaigns/CAMPAIGN_ID/test -H "$KEY" -H 'content-type: application/json' \
  -d '{"to":"[email protected]","allSteps":true}'

curl -X POST $API/campaigns/CAMPAIGN_ID/launch -H "$KEY"
Then what? Watch replies with GET /inbox or the email.replied webhook. Answer with POST /inbox/:id/reply. Check quotas and rate-limit headroom with GET /limits. The full reference is at /v1/docs on your API.

Try it on your own mailbox.

Your first month is free. Create a key and run the four steps above.

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