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

169 points by Haakam21 112 days ago | 169 comments

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 112 days 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

davchana 111 days ago | |

The only problem I have experienced few times with those unique email addresses is, sometimes they/utilities ask me to email from my official email address, and my setup is a catch-all, so I have to log in my pc at home, set up that address, send email.

OJFord 111 days ago | | |

That's a problem of your provider needing you to have received email at a particular address (or else doing whatever you do on the PC at home) before you can send from it; not something inherent in unique addresses.

I just type in whatever address I want to send from, and then as long as the domain is verified in SES it'll go through.

TheTaytay 112 days ago | |

That looks really interesting! Thanks for writing and sharing it!

frimmy 111 days ago | |

Fancy == tickled

MattDaEskimo 112 days 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

mhykim 112 days ago | |

Fair concern, and I agree on the end state. Agents will eventually use native agent-to-agent protocols.

The question is the transition, because email is undoubtedly the most ubiquitous channel of communication in today. I would only give my agent an A2A integration if your agent has an A2A integration, but because you don't we are at a stalemate. I'd rather just give my agent an inbox where I know it can communicate with the other billions of people that already have an email address.

Email isn’t the final protocol for agents. It’s the bridge that lets them participate in today’s internet while native agent protocols/networks emerge.

KludgeShySir 111 days ago | |

And you probably don't want to dump the emails first thing into the agent's context. You should insert a cup of coffee and the morning newspaper into the context, and only then the emails.

suriya-ganesh 112 days 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?

mhykim 112 days ago | |

We do have robust checks in place to catch spam and bad actors(reputation, SPF DKIM DMARC, etc.) but as with all tools there will be bad actors who come up with creative ways to scheme for nefarious purposes.

We expect our infra and policies to evolve with usage, and one of our goals is to make agent driven email safer than the status quo, not just more scalable

bofadeez 112 days ago | | |

But as of now you're just wide open for abuse? Okay

Resend uses SES since it's almost impossible to get private IP mail to hit the inbox through ProofPoint filters. Looks like you have no idea about any of this. You don't even have knowledge of email reputation, much less a plan. Have you heard of Senderscore? You will have all zeros. Saying "SPF DKIM DMARC" is wild - that's a checklist from 15 years ago.

themanmaran 112 days ago | |

I don't think they use the agentmail domain for sending emails. Users connect their own domain and manage reputation (similar to all the other email marketing tools)

smpandya 112 days 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?

Haakam21 112 days ago | |

Network effects - agents need to meet humans where they already work. Would rather use something standard than bespoke.

trollbridge 112 days ago | | |

And how long will humans and agents be communicating over email?

We have strict rules for our customer service people not to respond to what seems to be a bot, since all the "agent" based communication we get is for conducting scams. It is never worthwhile to engage with or pursue.

If we lose a sale or two, that's okay.

jessechoe10 112 days 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)?

Haakam21 112 days ago | |

Yup think there is plenty of ways the product can evolve evolve

nerdsniper 112 days 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.

Haakam21 112 days ago | |

Because we built the same inbox infrastructure as Gmail. Inboxes have threads, threads have messages, messages have attachments. You can search, label, filter, reply, forward. None of this comes out of the box with SES.

trollbridge 112 days ago | | |

Couldn't someone just ask Claude Code to make an email system with threads/messages and handle attachments?

Doesn't seem like a particularly difficult problem to solve.

benswerd 112 days ago | | |

I didn't get it until you said this

biddit 112 days 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.

gustrigos 112 days ago | |

We are using AgentMail for sourcing quotes here at scale with various top shippers. It’s not about letting the agent act in fully deterministic ways, it’s about setting up the right guardrails. The agents can now do most of the job, but when there’s low confidence on their output, we have human in the loop systems to act fast. At least in competitive industries like logistics, if you don’t leverage these types of workflows, you’re getting very behind, which ultimately costs you more money than being off by some dollars or cents when giving a quote back.

biddit 112 days ago | | |

Okay that makes sense.

Do you see more pushback in specific industries? I did some quote/purchasing automation work in food mfg a decade ago, and those guys were super difficult to work with. Very opaque, guarded, old-school industry.

Haakam21 112 days ago | |

This refers to B2B use cases that are live in production. Finding, contacting, and negotiating with vendors is a tedious process in many industries. In the time a human reaches out to 10 vendors, an agent reaches out to 100 or 1000. So it finds deals that a human would not have.

fmbb 112 days ago | | |

But if you hire ten or 100 real humans you have accountability and the same number of contacts per day?

Are logistics companies really that poor so they cannot afford to pay workers wages?

trollbridge 112 days ago | | |

Once vendors are getting AI spam sent to 1,000 of them and their competitors, they will stop responding and find other sales channels. This won't be sustainable.

petervandijck 112 days 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.

pizzafeelsright 112 days 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.

pirsquare 112 days 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.

adisingh13 111 days ago | |

thank you, this means a lot!

Jayakumark 112 days ago |

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

adisingh13 112 days ago | |

we have a few things in place, allowlists and permissions act as a layer. also beginning some work on prompt isolation within api soon. but having an isolated identity + data within a separate agentic inbox also puts less risk of your personal email data being injected - which is most people's main concern

brap 111 days ago | | |

>prompt isolation

You mean isolating data from instructions? As far as I know this is not a solved problem, or is it?

gpmcadam 111 days ago | | |

Where do you configure the allowlists?

pbronez 112 days 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.

Haakam21 112 days ago | |

Thats why we built it :) We have an integration with n8n, will build one for Glean

thedrake 112 days ago | | |

and a request for gumloop. (a YC alum) https://docs.gumloop.com/

adisingh13 111 days ago | |

i'd love to know more about these use cases. open to chatting sometime? adi@agentmail.cc is my email

charles_f 111 days 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.

neumann 111 days ago | |

likewise

rnc000 107 days ago |

I've been working for some time on a similar project, which I open-sourced yesterday, Apache 2.0 licensed if anyone cares to contribute or use https://nornweave.datacovey.com/

swaraj 112 days 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

Haakam21 112 days ago | |

We have had some users get banned from Gmail for using it Clawdbot. Regardless our API is way more agent friendly and I think your Clawdbot would agree.

moomoo11 111 days ago |

This is pretty cool. You could apply this to so many things, like automating procurement managers, fulfillment agents, or customer support for e-commerce.

Haakam21 111 days ago | |

Yes lots of use cases!

lucasayb97 112 days 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

Haakam21 111 days ago | |

Thanks, yes we are continuously learning

gpmcadam 111 days ago |

The idea here is great and I think it has a lot of legs but I think inherently people will have initial concerns with security.

Do you have plans to only allow reading mail from specific senders, and giving fine-grained control on the API side?

I would like to give this to an AI agent but only initially where I and my team can forward mail to the agent, and not give it the ability to draft and send emails on its own.

Haakam21 111 days ago | |

Yes we are adding for email/domain allow/blocklists. Same for fine-grained permissions.

digitcatphd 111 days ago |

This is fantastic! I created a GMAIL for my Clawdbot and Google deleted the account after an hour.

Haakam21 111 days ago | |

Happy we could provide a solution!

dshah 111 days ago |

Congrats on the launch. Sign-up was super smooth and the product is compelling.

Will be testing it with some of the agent work I'm doing on agent.ai.

If you're ever looking for a super low-maintenance indie investor, please reach out. Have lots of YC folks that will vouch for me.

thetwopct 111 days 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?

nubg 112 days 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?

smoyer 111 days ago |

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

adisingh13 111 days ago | |

We know the founder of this pretty well actually. It's not really an alternative. They are an MCP that is building an email-like layer for coding agents to talk to each other. We are an actual email inbox provisioned via API for agents to email agents or humans.

wild_egg 112 days 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

themanmaran 112 days ago | |

We build "long running" email agents. But it's not really long running in the sense of an agent taking 1000's of actions in a giant loop.

It's more "long running" because the agent takes 4 steps, then waits a week for the user to email it back. We might have a successful client exchange that takes a month, but for the Agent it's 99% just waiting for the next user reply.

Haakam21 112 days ago | |

Hmm why do you say that? Would love to hear your thoughts

throw03172019 112 days 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.

ckenst 112 days ago | |

Why didn't you just use something like Mailinator? They specialize in this exact thing. Gives you an API to grab links and everything. That's what I use.

Haakam21 112 days ago | |

Yup plus webhooks are overkill for this. Need to set up a public HTTP server and pass messages to your agents. With websockets you can open connection right from your agent and close it in seconds once the 2FA code is delivered.

trollbridge 112 days ago | |

... you had to use Zapier to extract an email from an inbox?

iamacyborg 112 days ago | | |

Google API scopes for email are pretty restrictive, which is generally a good thing from a security perspective.

umrashrf 112 days ago |

So AgentMail uses Mail Agent

mhykim 112 days ago | |

Nope AgentMail is its own infra. Not a single line of Gmail/Outlook code in the codebase

CuriouslyC 111 days 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!

Haakam21 111 days ago | |

That is a compelling use case

ncrmro 112 days 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

brap 111 days ago |

I see a lot of folks are excited about this but I genuinely don’t quite get it, pretty sure I’m missing something. ELI5, why is this useful?

Imustaskforhelp 112 days 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.

adisingh13 112 days ago | |

thanks for the input, we always appreciate constructive feedback!

lasgawe 111 days ago |

I like the design of the web site btw

Haakam21 111 days ago | |

ty :)

chasd00 112 days 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.

Haakam21 112 days ago | |

This is a good point. We have anti-spam measures in place and allow users to configure allow/blocklists to mitigate attacks.

trollbridge 112 days ago | | |

What about a concerted attack?

Spam doesn't matter for an agent mailbox, but sophisticated fraud does.

rootnod3 112 days ago | |

Can't wait for agents to change the code they are building to buy Amazon Point cards at Target and send the codes back.

johnsillings 112 days ago |

super cool launch – congrats!

ritomsen09 112 days ago |

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

mhykim 112 days ago | |

Email is already the internet’s identity layer. By giving agents their own inbox they don't need to borrow human identity rather act as first class actors on their own.

It lets agents plug into the same trust systems the web already uses! And this opens the door to new ways agents can do work and build credibility on the internet.

Haakam21 112 days ago | |

The nice thing about email is that identity verification is already built in. In fact online identity is based on email.

mrklol 112 days ago |

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

ktanishqk 112 days ago | |

> Because we built the same inbox infrastructure as Gmail. Inboxes have threads, threads have messages, messages have attachments. You can search, label, filter, reply, forward. None of this comes out of the box with SES.

aws just gives you a low-level smtp + api service. we are the application layer they do not offer but your agents need to actually use email as first-class users.

yard2010 112 days ago | |

This alone doesn't give you gmail UX - threads, inboxes, tagging, etc.

mpeg 112 days ago | |

No offence, but this reads to me like the classic dropbox HN comment

The idea is pretty solid, automation platforms often provision a mailbox per flow for this reason, so it makes sense to make a generic service that can be used through MCP for agents

keeganpoppen 111 days ago |

i think they figured this out in the unix era

adammiribyan 112 days ago |

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

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

rnc000 112 days ago | |

how's traction going? Do you worry about some open-source project replacing it?

rippeltippel 112 days ago |

Finally agents can spam other agents, instead of humans.

Haakam21 112 days ago | |

I think agentic email communication can be productive as well!

alongub 112 days ago |

AgentMail looks amazing!

wild_egg 112 days ago |

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

ktanishqk 112 days ago | |

yup, hard to do that too. AgentMail actually gives agents email addresses and treats them as first class inbox owners with the capability of sending and receiving emails with any other email address.

the mcp agent mail project is agents getting their own identity in an internal messaging layer.

x_ulla 111 days ago |

Looks cool

dbushell 112 days ago |

Dead internet theory.

calvinmorrison 111 days ago |

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

waynenilsen 112 days ago |

amazing now do the same for voice and sms!

stronglikedan 112 days ago | |

Done. Texts can be sent to email addresses and texts can be sent via email, and you can dictate texts and have them read back to you with text-to-voice.

Haakam21 112 days ago | |

We have gotten a lot of requests for SMS. Seems like a natural next step.

waynenilsen 112 days ago | | |

i think when someone makes the cli like this they're going to win

$ phone call bill

ok call_id=3f2a

$ phone status 3f2a

dialing

$ phone status 3f2a

answered

bill: hello

$ phone say 3f2a "hey, quick question"

singpolyma3 112 days ago | | |

Good luck getting this past A2P campaign registration rules...

keepamovin 112 days 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

Haakam21 112 days ago | |

Nice seems like we are building towards a similar vision. Would love to collaborate!

keepamovin 112 days ago | | |

Sure, bud. Cut me in on your 500K!

My Show from 14 days ago: https://news.ycombinator.com/item?id=46629191 - hmm, why didn't it get into YC?

rootnod3 112 days 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?

Haakam21 112 days ago | |

Taking a look will make a fix asap

whytaka 111 days ago | | |

Can I ask how you made the animations in the Use Cases section?

trollbridge 112 days ago | | |

This is just a graphic design gripe, but on:

https://www.agentmail.to/enterprise

the cutesy ASCII art is rendered in a proportional, not monospace, font, so it looks terrible.

rootnod3 112 days ago | |

Love getting downvoted for mentioning that the website doesn't properly load and reeks of vibe coding :D

If that's the quality y'all can live with and accept, no wonder the web turned to shit.

kasane_teto 112 days ago | | |

trvth

acedTrex 112 days ago | |

I can smell it from here tbh

rootnod3 112 days ago | | |

Called it! https://www.ismscopilot.com/isms-copilot-cookie-policy

Imustaskforhelp 112 days ago | |

The website is really bad. If one moves from Python to curl in the website, one really sees how much noticable lag there is.

Like holy Cow, I am not sure what to say seeing such noticable lag

The time to go from python to curl. I have seen websites load faster, heck I feel like even 2-3 whole websites can actually be loaded in the noticable lag time we observe.

Absolutely crazy to witness.

rootnod3 111 days ago | | |

I have a strong guess on how that website was coded....

HarryDu 112 days ago |

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

Haakam21 112 days ago | |

Don't know about all but certainly a significant proportion!

kushbhuwalka 112 days ago |

lets goooo