Platform capabilities

The AI first outbound platform

Cold email sequences and calendar invite campaigns, both sending from your own Google Workspace mailboxes, both written by an AI provider you choose and pay directly, and both piping every event onward through webhooks and n8n.

See a demo
2
Outreach engines
Unlimited
Sending mailboxes
9
Reply intents detected
7
Languages classified

01 · Cold email

Sequences that stop when they should

Build a multi step sequence with per step delays from same day out to a year. Choose template copy or let AI write each message from the recipient website. Anyone who replies drops out automatically.

Campaign sequence
Sample data
1Day 0Question about {{company}} hiring plansAI personalized4,820 sent312 replies
2Day 3Re: question about {{company}}A/B, 2 variants4,102 sent204 replies
3Day 7Worth a look?Template3,640 sent121 replies
4Day 14Closing the loopTemplate3,180 sent78 replies
Window: 09:00 to 17:00, recipient timezoneCaps: 50 per day, 25 per hour, per mailboxStops on reply

A/B variants per step

Run two versions of any step. A daily job picks the winner on reply rate so the better copy takes over without you watching it.

Validation before enrollment

Syntax, MX, and role address checks run before a contact enters a sequence. Anything questionable is quarantined instead of sent.

Suppression that sticks

One click unsubscribe headers on every message, plus a suppression list checked before every single send.

02 · Replies

An inbox that triages itself

Replies land in a shared threaded inbox with intent already labelled across nine categories and seven languages. Bounces are parsed and suppressed. You read the ones that matter.

Inbox
Sample data
Dana Whitfield · Northwind Logistics
Interested12m

This is timely, we are reviewing vendors this quarter. Can you send pricing?

Marcus Lee · Farrow Health
Pricing objection48m

Interesting, but this is out of budget for us right now.

Sofia Ramirez · Kestrel Group
Referral2h

Not me, but you should talk to our ops lead. Copying her here.

Peter Nowak · Bracken Industrial
Timing objection3h

Revisit this in Q3 please, we are mid migration until then.

Automatic reply · Vantive Systems
Out of office5h

I am out of the office until the 14th with limited email access.

No open tracking. On purpose.

Open pixels drag down deliverability and inflate a number almost nobody acts on. Tantra measures clicks through a signed link on your own tracking domain, plus replies, reply intent, bounces, and unsubscribes. Those are the signals worth routing to a person.

03 · Calendar outreach

Invitations, not another email

Tantra creates a Google Calendar event and adds recipients as attendees, so Google delivers the invitation and it lands on their agenda. RSVP is the engagement signal, reconciled every 10 minutes and pushed to your CRM.

Calendar campaigns
Sample data
CampaignTagStatusInvitedYesMaybeNoPendingEvent date
Product webinar, March cohortwebinarActive18,4204,3181,1021,20411,796Mar 14, 2026
Enterprise demo series, set AdemoActive9,6402,2846107426,004Mar 18, 2026
Partner enablement workshoppartnerDraft00000Apr 2, 2026

Distributed across senders

Campaigns up to 50,000 contacts are split across your sender pool automatically, in batches, with retry on failure.

RSVP straight to your CRM

Accepts, declines, and tentatives are reconciled every 10 minutes and delivered by webhook to any endpoint you configure.

WebinarGeek sync

Sync broadcasts and subscribers, invite registrants automatically, and report on attendance in the same place.

04 · AI layer

Your key, your model, your prompt

Connect OpenRouter, Cerebras, or Novita and Tantra uses your key for every generation. There are no AI credits to buy from us and no markup on inference. Every call is logged so you can audit both cost and prompt.

AI provider
Sample data
OpenRouterDefault
openai/gpt-4o-mini
Cerebras
llama3.1-8b
Novita
llama-3.3-70b-instruct
System prompt

Write like a founder emailing a peer. Two sentences of context from their site, one specific question. No superlatives.

Generated for one recipient
Sample data
Source
northwind-logistics.example.com
Subject
Your new Rotterdam depot
Body

Hi Dana, I saw Northwind opened the Rotterdam depot in January and is hiring dispatch coordinators for it. Usually that means route planning is about to get painful. How are you handling driver comms across the two sites right now?

Logged for cost and prompt audit

Run Tantra from Claude or Cursor

Tantra ships an MCP server, so any MCP capable AI client can drive it as a native tool. Ask Claude to list your campaigns, import a contact list, pull dashboard metrics, or launch a campaign, in plain language.

05 · Deliverability

Domain health, checked daily

Every sending domain is scanned each day for SPF, DKIM, DMARC, and DNSBL listings and scored, so a problem surfaces here before it surfaces in your reply rate.

Domain health and senders
Sample data
Overall
94/100
SPF
Pass
DKIM
Pass
DMARC
Quarantine
DNSBL
0 listings

Sender performance

Per mailbox, with warmup state

MailboxSentRepliesReply rateBounceWarmup
sender-01@yourdomain.example.com1,450946.5%0.7%Warmed
sender-02@yourdomain.example.com1,380825.9%0.9%Warmed
sender-03@outreach.example.com1,290715.5%1.1%Warmed
sender-04@outreach.example.com620386.1%0.6%Warming

06 · Compliance

Unsubscribe and suppression

One click unsubscribe headers on every message, and a suppression list checked before every send. Block individual addresses, whole domains, top level domains, or role mailboxes, and bulk import existing lists by CSV.

Suppression
Sample data
AddressesDomainsTop level domainsRole mailboxes
ValueReasonAdded
optout@example.comOne click unsubscribeMar 4, 2026
info@example.orgRole mailboxMar 3, 2026
example.netDomain blockMar 1, 2026
bounced@example.comHard bounceFeb 27, 2026

07 · Integrations

Webhooks, n8n, and anything downstream

Tantra emits a typed event the moment something happens and POSTs it to any endpoint you configure. Wire that into n8n, Zapier, or Make and drive whatever comes next: the CRM record, a LinkedIn touch in your own tooling, a Slack alert, an enrichment step. Those actions run in your automation tool, not inside Tantra, so you are never limited to the integrations we happened to build.

Typed events, delivered reliably

email.sent, email.replied, email.clicked, email.bounced, email.unsubscribed, email.intent.classified, email.sequence.completed, and lead.stage.changed, plus RSVP updates from calendar campaigns. Retried and deduplicated so a flaky endpoint costs you nothing.

REST API with scoped keys

Issue API keys scoped to exactly what an integration needs, across campaigns, contacts, and webhooks. Revoke any key without touching the others.

n8n, Zapier, and Make

Point a webhook at your automation tool and take any action from there: create the CRM record, queue a LinkedIn touch, alert Slack, enrich the contact, append a row, or call your own service.

Google Workspace and WebinarGeek

Service account connection for sending, plus broadcast and subscriber sync for webinar programs. Microsoft Calendar is coming soon.

Webhook
Sample data
ACTIVE
12,480 deliveries
Endpoint
https://hooks.example.com/tantra
{
  "event": "reply.received",
  "campaign": "Q1 outbound",
  "contact": "dana@example.com",
  "intent": "interested",
  "leadStage": "engaged",
  "score": 42
}

Both engines. Every mailbox you own. One price.

Start on the free plan and connect your first mailbox today.

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