Introducing CarlyEmail: Give Any AI Agent an Inbox
We built CarlyEmail because every agent we shipped needed the same missing piece: a real place to receive mail. Not a webhook that fires once and forgets, but an address people can write to, a thread that stays intact, and a reply that lands inside the conversation instead of beside it.
CarlyEmail is that layer, and it does not care what you built your agent with. LangChain, the OpenAI Agents SDK, the Claude Agent SDK, the Vercel AI SDK, Mastra, Cloudflare Agents, or your own runtime all work the same way.
An address in one call
npm install carlyemailimport { CarlyEmail } from "carlyemail";
const carly = new CarlyEmail();
const inbox = await carly.inboxes.create({ username: "hello" });
const { messages } = await carly.messages.list(inbox.email);
await carly.messages.reply(inbox.email, messages[0].message_id, { text: "On it." });There is a Python package, a CLI (npx carlyemail signup), and a plain REST API that do the same three things. Nothing to provision in a dashboard, no waiting on a support ticket for a sending domain.
What comes with the address
Threads. Replies are matched to the conversation they belong to, including the ones Outlook mangles on the way through.
Events. A signed webhook or WebSocket message fires the second mail arrives, carrying a thread_id that resumes the right agent conversation.
Attachments. In and out, up to 25 MB.
Your own domain. SPF, DKIM, and DMARC configured for you, on dedicated sending infrastructure with per-organization reputation tracking and automatic suppression of bounced and complained addresses.
MCP. Point any compatible client at https://api.carlyemail.com/mcp and the whole inbox becomes live tools.
What people are building with it
A coding agent you email a task to and get a pull request back. A support desk that answers from your docs and hands the rest to a person without dropping the thread. A per-tenant inbox for every customer in a product, provisioned from code at signup.
Free covers 3 inboxes and 1,000 emails a month with no card. Paid plans start at $20/month and raise the volume, not the feature set: every tier gets the whole API.
If you are still choosing a platform, our rundown of email APIs for AI agents walks through the four problems that eat the sprint. Then get an address at carlyemail.com.
Ready to automate your busywork?
Carly schedules, researches, and briefs you—so you can focus on what matters.
See what people say
"Before Carly, I relied on a Calendly link, but the whole process felt impersonal and not very professional. Carly changed that by handling all the back-and-forth, so I'm no longer stuck in endless email threads trying to line up schedules.
Now Carly reaches out to candidates, shares my real-time availability, lets them pick a slot, then sends a Zoom link and drops it straight into my calendar. She sends reminders to both of us before each call, which has significantly reduced no-shows and last-minute confusion.
On top of scheduling, Carly acts like a full executive assistant, sending me my schedule the night before so I can prepare for each call. It reminds me of the old x.ai assistant, but Carly is noticeably smarter, faster, and better suited to my healthcare recruitment business."
