Inkbox: Email, Phone and iMessage Identities for AI Agents
Inkbox gives AI agents an identity of their own. Each agent you create gets an email inbox, and can also get a phone number for calls and texts, iMessage, WhatsApp, Slack, a public web address and a vault for credentials, all managed through one API. As of November 2026, Inkbox will also run the agent for you on its own cloud computer. It’s a San Francisco company from Y Combinator’s Summer 2026 batch, and it has nothing to do with the tattoo brand of the same name.
The quick answer: Inkbox is one of the broadest agent communication platforms we’ve seen, bundling email, voice, texting and iMessage under one identity, with a free plan that covers three agents. It suits developers who want one place to give agents a full set of contact channels rather than stitching together separate email, phone and messaging providers. A disclosure first: we make Carly and CarlyEmail, which overlap with Inkbox’s phone and email features, so we’ve kept to facts from Inkbox’s own pages and linked them.
Inkbox at a glance
Checked against Inkbox’s site, docs, pricing and YC profile on November 12, 2026.
| Inkbox | |
|---|---|
| What it is | An identity and communication layer for AI agents: email, phone, iMessage, WhatsApp, Slack, tunnels and a credential vault |
| Company | Vectorly, Inc., doing business as Inkbox, San Francisco |
| Founders | Ray Liao (CEO), Alex Wilcox (CTO) and Dima Vremenko |
| Funding | $5.3 million seed, November 2026, led by Peak XV with Pioneer Fund and Y Combinator |
| Plans | Free (3 agent identities), Developer (10), Startup (100), Enterprise |
| Developer access | Python, TypeScript and Rust SDKs, a CLI, an MCP server, webhooks |
| Open source | SDKs and examples on GitHub under an MIT license |
| Best for | Developers giving agents several ways to be reached, from one API |
What an Inkbox identity includes
Inkbox’s central idea is the identity. Its pricing page describes one as “its own communication surface: a mailbox, optionally a phone number and iMessage support, a publicly reachable internet address (via tunnel) for receiving incoming traffic,” plus access to shared contacts and credentials. In practice, an identity is one agent’s presence in the world.
Here’s what can hang off an identity, per Inkbox’s docs:
- Email: an inbox on Inkbox’s own domain by default, or on a domain you own, with threads, drafts, signatures and IMAP and SMTP access so you can open it in a normal mail app.
- Phone: one number per identity for calls and texts, with Inkbox Voice AI answering calls by default.
- iMessage: through a shared Inkbox router or a dedicated line.
- WhatsApp and Slack: WhatsApp on an approved dedicated number, and a Slack connection that can search history and act in conversations.
- Tunnels: a stable public URL that routes web, WebSocket and raw TCP traffic to wherever your agent runs.
- Contacts, notes and a vault: a shared contact directory, searchable notes and encrypted credential storage across your agents.
- Agent-to-agent: an identity can be reached by other agents over the A2A protocol.
There’s also a feature for setup: an agent can sign itself up for Inkbox with no account or API key, and open a support task with Inkbox’s own support agent if it gets stuck.
Phone calls and Inkbox Voice AI
Each identity can have one phone number, and agents can place and receive calls. New identities answer incoming calls with Inkbox Voice AI, currently in beta, which needs no server or code. You can also hand an outbound call to it with a plain-language reason, and it “works the errand, records action items, and delivers the whole package”: transcript, outcome and action items.
If you’d rather run your own voice agent, Inkbox connects to your WebSocket when a call starts. By default it handles speech-to-text and text-to-speech, so your agent only deals with text, though you can opt out and handle audio yourself. Incoming calls can be auto-accepted, screened by your webhook, answered by Voice AI or forwarded to another number. Texting from Inkbox’s US numbers runs under 10DLC carrier registration, which Inkbox can manage for you.
iMessage on Inkbox
Inkbox offers iMessage in two forms, and the difference matters:
- Shared service. Included on every plan. A person connects to your agent by texting Inkbox’s shared iMessage router, and the conversation is assigned to your agent. The person always starts the conversation, and shared service only supports one-to-one chats.
- Dedicated line. Included on the Startup plan and available on Enterprise. It belongs to your organization, can start new conversations, and supports group chats of 2 to 8 people.
Inkbox’s iMessage docs cover tapbacks, read receipts, typing indicators and media. Dedicated lines can also receive messages from email-based iMessage addresses, though those conversations are receive-only. The plans cap how many people a shared setup can talk to at once: on the free plan, three unique recipients at a time.
We didn’t find an explanation in Inkbox’s docs of how its iMessage service runs behind the scenes. Every iMessage provider depends on Apple, which doesn’t offer a public iMessage API, so it’s worth asking any vendor how lines are run and what happens if one is flagged.
Hosted agents
Inkbox’s newest product goes beyond communication. In its seed announcement on November 9, 2026, it launched hosted agents: you pick an agent harness, such as Hermes or Codex, give it instructions, and it gets its own cloud computer tied to its Inkbox identity.
The problem Inkbox is solving is a familiar one for anyone who has built an email agent. “Any agent can send an email with one API call. But replies don’t arrive on your schedule,” the announcement explains. A hosted agent sleeps when idle and wakes for every email, text, iMessage, WhatsApp or Slack message it’s set to handle. It can also run on a schedule, keeps its files between sessions, and asks before using a tool unless you let it act on its own. Its access is limited to its own identity, and the contact rules you set still decide who it can talk to.
Plans
Inkbox’s pricing page has four tiers, with annual billing available at two months free.
| Plan | Price | Agent identities | Phone and iMessage |
|---|---|---|---|
| Free | $0 | 3 | Shared iMessage (up to 2,000 messages a month), 30 call minutes in total |
| Developer | $30/month | 10 | Shared iMessage, plus 1 dedicated phone number for calls and SMS |
| Startup | $200/month | 100 | 1 dedicated iMessage line, 9 dedicated phone numbers, higher allowances |
| Enterprise | Custom | Custom | International numbers, dedicated iMessage infrastructure |
Every plan includes email inboxes, a public URL, agent-to-agent messaging, contacts and the vault. Texts and calls above the included allowances are billed by usage, and the included allowances cover the US and Canada. The dedicated phone numbers on Developer and Startup are VoIP lines for calls and SMS, not iMessage. Only the Startup plan’s dedicated iMessage line can message people who haven’t texted first.
Who’s behind Inkbox
Inkbox was founded in 2025 and went through Y Combinator’s Summer 2026 batch, according to its YC profile. Ray Liao, the CEO, has a computer science PhD from MIT and previously co-founded Empallo, an AI virtual clinic for cardiovascular care. Alex Wilcox, the CTO, worked in machine learning engineering and computer networking research. Dima Vremenko built machine learning pipelines for clinical prediction at Harvard Medical School.
The $5.3 million seed round was led by Peak XV, with Pioneer Fund and Y Combinator taking part. Angel investors include Vercel CEO Guillermo Rauch, Privy CEO Henri Stern, Databricks chief AI scientist Jonathan Frankle, Linear COO Cristina Cordova and Accel partner Dan Levine. Inkbox says it has processed “millions of messages for AI agents” and that “tens of thousands of users” have given an agent an Inkbox identity since its YC launch about four months earlier. Those are company figures.
What to weigh
A few things worth knowing before you commit:
- Breadth versus depth. Inkbox covers more channels than any single-channel provider, which is convenient. If one channel is your whole product, compare it against specialists in that channel.
- iMessage reach. Shared iMessage requires people to text first and caps how many recipients a setup can talk to at once. Starting conversations takes a dedicated line, which begins on the Startup plan.
- Beta features. Inkbox Voice AI and hosted agents are new, and Voice AI is labeled beta.
- Security details. We didn’t find a published security certification on Inkbox’s site. If you’ll route sensitive email or calls through it, ask how content is stored and who can access it.
How Inkbox compares
Inkbox overlaps with two kinds of tools. For agent email, the closest comparisons are AgentMail and OpenMail, which focus only on inboxes. For texting and iMessage, the managed iMessage providers each have a different angle:
- Linq: the infrastructure behind many consumer assistants, with managed load balancing across lines.
- Blooio: self-serve lines for small businesses and agencies, plus Apple Messages for Business.
- Photon: open source, reaching iMessage, WhatsApp and Telegram from one codebase.
- Chert: iMessage plus FaceTime audio and video calls for agents.
- ZeroSettle: iMessage-only numbers with a hosted agent and Sign in with iMessage.
Inkbox’s pitch is that you shouldn’t need to choose: one identity carries email, phone, iMessage and the rest.
Who Inkbox suits
Inkbox is a good fit if:
- You’re building agents that need to be reachable several ways, by email, phone and text, and you want one API for all of it.
- You run many agents and want each to have its own inbox, number and credentials, with shared contacts and notes.
- You’d like the agent hosted too, so it wakes up when a reply arrives instead of running around the clock.
Look elsewhere if:
- You need iMessage outreach at scale on a small plan. Starting conversations takes a dedicated line.
- One channel is your whole product and you want a specialist’s depth there.
- You need a published security certification before you start.
If what you actually need is a set of email inboxes for your agents, that’s what our CarlyEmail does. And if you want an AI on your business phone that answers calls and texts customers back, without building an agent at all, Carly does that out of the box from inside ChatGPT or Claude. Our guide to giving an AI agent an email address explains the email side.
FAQ
Is Inkbox the tattoo company?
No. Inkbox AI, the subject of this page, is an agent communication platform run by Vectorly, Inc. in San Francisco. It’s unrelated to the semi-permanent tattoo brand called Inkbox.
What does Inkbox give an AI agent?
Each agent identity gets an email inbox, and can also get a phone number, iMessage, WhatsApp, a Slack connection, a public URL through a tunnel, agent-to-agent messaging, and access to shared contacts, notes and a credential vault.
Does Inkbox have a free plan?
Yes. The free plan covers three agent identities, each with an email inbox and shared iMessage, plus 30 call minutes in total.
Can an Inkbox agent answer phone calls?
Yes. New identities answer calls with Inkbox Voice AI by default, or you can connect your own voice agent over a WebSocket, forward calls, or screen them with a webhook.
Can Inkbox agents start iMessage conversations?
Only on a dedicated iMessage line, which comes with the Startup plan and Enterprise. On shared iMessage, people have to text your agent first.
Who invested in Inkbox?
Inkbox raised a $5.3 million seed round in November 2026, led by Peak XV with Pioneer Fund and Y Combinator, plus angels including Guillermo Rauch of Vercel.
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