Create an inbox with one request. Get every reply pushed to a webhook. Answer in the same thread. Free for 3 inboxes and 100 messages a day - no card.
For agents: https://app.ackuna.com/llms.txt
The whole integration, end to end. Each call is one request against the v1 API.
No console, no human. Ackuna mails an 8-character code to the address; POST it back to /v1/signup/verify with the returned signup_id and you get the organization and your first key.
curl -X POST https://app.ackuna.com/api/v1/signup \
-H "Content-Type: application/json" \
-d '{"email": "[email protected]", "organization_name": "Robot Co"}'Omit domain and the inbox is hosted on the shared platform domain, so it can receive mail immediately. Pass a domain you control to host it there instead.
curl -X POST https://app.ackuna.com/api/v1/inboxes \
-H "Authorization: Bearer ak_..." \
-H "Content-Type: application/json" \
-H "Idempotency-Key: create-support-inbox-1" \
-d '{"username": "support"}'Every message that lands in one of your inboxes is pushed to your endpoint as an inbox.message.received event, signed so you can verify it came from us.
curl -X POST https://app.ackuna.com/api/v1/webhook-endpoints \
-H "Authorization: Bearer ak_..." \
-H "Content-Type: application/json" \
-H "Idempotency-Key: register-agent-webhook-1" \
-d '{"url": "https://agent.example.com/webhooks/ackuna", "event_types": ["inbox.message.received"]}'reply_to_message_id is enough - the recipients, the subject and the threading headers are all inferred from the message you are answering.
curl -X POST https://app.ackuna.com/api/v1/inboxes/inb_01k2n9v8qf3m7d5b0y6xz4rt3e/messages \
-H "Authorization: Bearer ak_..." \
-H "Content-Type: application/json" \
-H "Idempotency-Key: reply-to-msg-1" \
-d '{"reply_to_message_id": "msg_01k2n9v8qf3m7d5b0y6xz4rt5g", "text_body": "Thanks for reaching out."}'Newsletters, the SMTP relay and Agent Mail are on every plan. Paid plans share one monthly email allowance between them, so you are never charged for splitting your volume the wrong way.
Two months free on every yearly plan.
All three services on one workspace, no card
No credit card required
For a first production workload
Billed monthly, cancel anytime
For teams running all three services
Billed monthly, cancel anytime
For high volume across every service
Billed monthly, cancel anytime
| Plan | Free $0 forever | Builder $19 / month | Scale $59 / month | Startup $149 / month |
|---|---|---|---|---|
| Services included | All three | All three | All three | All three |
| Emails per month (shared) | Per service | 60,000 | 200,000 | 500,000 |
| Newsletter emails per day | 500 | 5,000 | 25,000 | 100,000 |
| Relay emails per day | 100 | 10,000 | 40,000 | 100,000 |
| Agent Mail emails per day | 100 | 2,000 | 10,000 | 50,000 |
| Contacts | 500 | 5,000 | 25,000 | 100,000 |
| Contact lists | 3 | 25 | 100 | 500 |
| Agent inboxes | 3 | 25 | 100 | 500 |
| SMTP credentials | 1 | 10 | 25 | 100 |
| Domains (sending + receiving) | 1 | 10 | 50 | 250 |
| Team seats | 1 | 3 | 10 | 25 |
| Workspaces | 3 | 3 | 5 | 10 |
| Relay log retention (days) | 3 | 30 | 90 | 180 |
| Relay body retention (days) | 1 | 7 | 14 | 30 |
Paid plans draw Newsletters, SMTP Relay and Agent Mail from one shared monthly email allowance. Free keeps a separate monthly allowance per service: 2,500 newsletter, 3,000 relay and 3,000 Agent Mail emails. Per-service daily caps apply on every plan. One domain allowance covers sending domains and Agent Mail receiving domains together.