Launch HN: AgentMail (YC S25) – An API that gives agents their own email inboxes

137 points by Haakam21 14 hours ago


Hey HN, we're Haakam, Michael, and Adi. We're building AgentMail (https://agentmail.to), the email inbox API for agents. We’re not talking about AI for your email, this is email for your AI.

Email is an optimal interface for long-running agents. It’s multithreaded and asynchronous with full support for rich text and files. It’s a universal protocol with identity and authentication built in. Moreover, a lot of workflow critical context already lives in email.

We wanted to build email agents that you can forward your work to and get back a completed task. The agents could act entirely autonomously as you wouldn't need to delegate your identity. If they did get stuck they could just send you, or anyone else, an email.

Using Gmail, we kept getting stuck on the limitations of their API. No way to create inboxes programmatically. Rate and sending limits. OAuth for every single inbox. Keyword search that doesn't understand context. Per-seat pricing that doesn't work for agents.

So we built what we wished existed: an email provider for developers. APIs for creating inboxes and configuring domains. Email parsing and threading. Text extraction from attachments. Realtime webhooks and websockets. Semantic search across inboxes. Usage-based pricing that works for agents.

Developers, startups, and enterprises are already deploying email agents with AgentMail. Agents that convert conversations and documents into structured data. Agents that source quotes, negotiate prices, and get the best deals. Agents that emulate internet users for training models on end-to-end tasks.

Here's demo of Clawdbots communicating using AgentMail: https://youtu.be/Y0MfUWS3LKQ

You can get started with AgentMail for free at https://agentmail.to

Looking forward to hearing your thoughts and feedback.

schappim - 9 hours ago

I'm 100% for this, but I think you can go even more granular than "gives agents their own inboxes".

Thanks to Action Mailbox in Rails[1], I give all my records email addresses. Eg let ecommerce "order" records accept forwarded emails that are pinned as comments. It opens you up for doing things like forwarding a purchase order and having the PO number pulled out and attached to an order, or forwarding tracking information from a supplier and having it attached to a "supplier order" etc.

In my personal life I have individual email addresses for all my utilities and emails automatically get filed away.

If this idea tickles your fancy, I opensourced Emitt[2], an inbound email processing server with LLM-powered automation.

1. https://guides.rubyonrails.org/action_mailbox_basics.html

2. https://github.com/schappim/emitt

asyncadventure - 5 hours ago

The transition timing here is key - while native agent protocols will eventually emerge, email provides the interoperability bridge we need today. Building on established infrastructure makes sense when you're solving the coordination problem of getting all agents to adopt the same communication standard. Rather than waiting for consensus on new protocols, using email lets agents participate in workflows immediately.

MattDaEskimo - 12 hours ago

I'm concerned that this fits in "using today's innovation to solve outdated paradigms".

Google has A2A: An Agent-to-Agent Protocol. SaaS is plumetting in value.

Arbitrary semantics made sense when communications were human-dominated.

If agents dominate these fields, why wouldn't they simply set their own protocols and methods to communicate both text, binary, and agreed data structures?

There's an assumption that email is somehow the best channel, when you've found yourself that the most popular, functional interfaces don't align with your expectations.

Then, ultimately I have a single agent that can sit in numerous communication platforms, such as email

suriya-ganesh - 10 hours ago

Interesting take, but this feels like one of those tarpit ideas that YC discourages their portco to start attacking.

Guaranteed this is going to attract a ton of abusers who are looking to use this for signing up to services, spamming or other nefarious purposes, which then blacklists the doman. This is an infinite whack-a-mole.

do you guys have some ways of handling it?

smpandya - 13 hours ago

Cool launch. Assuming you guys view email (and therefore SMTP) as becoming the de facto agent communication protocol in the long run. My question — why not something bespoke, similar to OpenAI’s Agentic Commerce Protocol or x402 from Coinbase?

charles_f - 3 hours ago

> Application error: a client-side exception has occurred while loading www.agentmail.to (see the browser console for more information).

I would advise to have the landing page static, or at the very least as something that can't crash entirely.

jessechoe10 - 11 hours ago

This is super interesting. Interesting to see how I'll be able to use this to help my customers with handling email responses. Gmail sucks for this. Super excited to see what you guys develop this into. Will this be able to eventually expand to other forms of agent communication (i.e. payment or phone numbers)?

- 2 hours ago
[deleted]
petervandijck - 10 hours ago

A pricing thought: if you keep the volume limits but do 10x the amount of inboxes per plan, I think that could be more attractive. For If I have 100s of agents that send limited email each.

biddit - 13 hours ago

> Agents that source quotes, negotiate prices, and get the best deals.

Didn't Alexa fail miserably with the "have AI buy something for me" theory?

There is a significant mental in allowing someone else make purchase decisions on my behalf:

- With a human, there is accountability.

- With deterministic software, there is reproducibility.

With an agent, you get neither.

FWIW - I am not anti-LLM. I work with them and build them full time.

pizzafeelsright - 10 hours ago

The moat for SaaS is gone.

I am 99% certain I could build to parity in a weekend using Cloudflare without the the pricing limitations.

I am thinking it would be within the free tier of CF usage.

I am not certain I have the bandwidth to communicate over delivery and plain text inspection concerns.

nerdsniper - 13 hours ago

How does this differentiate from a solution like AWS SES? (Which I assume AI Agents would be quite adept at using to send email)

I understand the differentiator vs GMail, but API-based scripted email access isn’t new.

smoyer - 4 hours ago

This is a pretty clear emergent pattern. An OSS alternative is https://github.com/Dicklesworthstone/mcp_agent_mail.

pirsquare - 10 hours ago

excellent idea, this will eventually be the SendGrid for email agents. Just automating 2FA alone is worth the gold. And there's tons of use cases.

I have no doubt this will be huge.

thetwopct - 5 hours ago

If the agent is sending emails to people you don’t know (“sourcing quotes”) wouldn’t this be a violation of Amazon SES (and all other email providers) terms? Dont they expect permission from the people you are contacting? How’d you get around that?

CuriouslyC - 7 hours ago

Seems like you're using email as a long lived task queue/journal system. Definitely optimizing for customer recognition/novelty over technical merits. Best of luck!

nubg - 8 hours ago

> Here's demo of Clawdbots communicating using AgentMail: https://youtu.be/Y0MfUWS3LKQ

Did you record yourself reading out the output of an LLM prompt in this video?

Jayakumark - 10 hours ago

If you know agents email address, it can still be Prompt Injected.. what prevention exists there ?

swaraj - 8 hours ago

Looked into this for my clawdbot, but ended up just using himalaya CLI connected to a new Gmail. Been working great so far - curious about what agentmail is better for

ncrmro - 9 hours ago

I’ve been looking at getting this going but stalwart mail, I have it setup but haven’t done much. I actually for now was thinking vpn only between me any my agents

wild_egg - 12 hours ago

> Email is an optimal interface for long-running agents.

Long-running agents are themselves not optimal though. There are a ton of these coordination layers for long running agents now but they don't make any sense under other paradigms

umrashrf - 12 hours ago

So AgentMail uses Mail Agent

throw03172019 - 13 hours ago

The 2FA via email case is great. I recently had to build a browser automation workflow that required 2FA. I ended up using Zapier to monitor email inbox and then extract the code and send back to our API. It was a bit slow.

lucasayb97 - 11 hours ago

It’s a really nice idea actually. There will be some concerns, maybe some mistakes, but it really works as a mean to communicate much easier with an agent

asyncadventure - 8 hours ago

This is fascinating - giving agents dedicated email addresses solves a real coordination problem in multi-agent workflows. I can see this being especially valuable for customer service automation where different agents need to maintain conversation continuity. Curious about how you handle email threading and context preservation across agent handoffs?

keeganpoppen - 5 hours ago

i think they figured this out in the unix era

johnsillings - 8 hours ago

super cool launch – congrats!

chasd00 - 13 hours ago

hah this is a great idea! sending email is such a common way to communicate and having agents with an inbox makes so much obvious sense. heh just don't let their addresses get out who knows how they'll respond to spam and phishing attempts.

mrklol - 12 hours ago

Looks like SES + api access, isn’t Amazon offering that already?

adammiribyan - 10 hours ago

Cool website. I built Croft a few weeks ago — very similar.

https://api.trycroft.com/landing-draft

rippeltippel - 13 hours ago

Finally agents can spam other agents, instead of humans.

ritomsen09 - 13 hours ago

How do you think this will help with identity verification in the future?

pbronez - 13 hours ago

Very interesting. I have a lot of enterprise AI use cases that would really benefit from being email native.

We’re an O365 GCC shop. Appreciate that your enterprise options include Bring Your Own Cloud, that makes things much easier for us.

It would be nice to have integrations with n8n and Glean.

alongub - 13 hours ago

AgentMail looks amazing!

- 11 hours ago
[deleted]
wild_egg - 13 hours ago

I guess not to be confused with https://github.com/Dicklesworthstone/mcp_agent_mail?

dbushell - 12 hours ago

Dead internet theory.

Imustaskforhelp - 9 hours ago

I have written in one of my comments here about how slow teh website is in one interacton

Then I scrolled even more in the website and the amount of lag, my my, I don't even know what to say but the amount of lag is something I have genuinely never witnessed in any website. This is like a new low. I really just want to archive this website to preserve how abysmally slow the website is and its aniations and everything. image literally loading 10% and everyhting.

Ship fast and break things is shying from what I am witnessing in here. Sfabt (ship fast and break things) is gonna use your service to talk to the agent which created this project to ask it personally to slow down

I can't view your website in 16 gigs of a computer... Weird where the world's progressing in this sense and how it got (YC funded?)

Quite frankly I am out of words for how slow the website is. Its really just that bad to be in its own league. Sorry to say.

waynenilsen - 13 hours ago

amazing now do the same for voice and sms!

calvinmorrison - 5 hours ago

congrats, I have been following you guys along for a while on LinkedIn. Good Luck

keepamovin - 13 hours ago

Hey I’m also working on this what a coincidence: https://ai-chat.email

Second time at least HN is launching YC on one of my products:

BrowserBox - hyperbeam

Mailpilot/AI-chat.email - agentnail

blobber2001 - 11 hours ago

[dead]

rootnod3 - 13 hours ago

"Application error: a client-side exception has occurred while loading www.agentmail.to (see the browser console for more information)."

> Looks at developer console...

- "Failed to create WebGL context: WebGL is currently disabled." Dafuq does an email website need WebGL for?

- "Cookie “dmn_chk_xxxxxxxx-yyyy-dead-beef-123456789ABC” has been rejected for invalid domain."

Let me guess...vibe-coded?

bitfrost - 8 hours ago

[dead]

HarryDu - 13 hours ago

In the future all the agent communication will be using agentmail!

kushbhuwalka - 13 hours ago

lets goooo