News for hackers. Stuff that matters.

Show HN: Agent.email – sign up via curl, claim with a human OTP

Hi HN! We're Haakam, Michael, and Adi from AgentMail- a ycs25 company. We give AI agents their own email inboxes. Recently, we ran an experiment called Agent.Email. It's a signup flow designed specifically for AI agents instead of humans.

The inspiration came from a few comments we received when we did our seed launch a few months back. They all came from the very apt observation that agents not being able to sign up to a product made for agents without human credentials was ironic and unideal.

This is basically the thesis we built AgentMail on: The internet was made for humans exclusively, designed to keep machines out by default.

Every signup flow assumes a browser, a person reading a page, and clicking a confirmation link. Unless agents can't do that, they can't be first class users of the internet.

Agents can now get an email inbox by themselves. (This also means a lot of email nobody wants to read gets processed by AI instead of your inbox being cluttered with spam and slop)

Here's how agent.email works.

Agent needs an inbox and hits AgentMail via curl. Agent receives instructions via MD unless the request comes from a browser, in which case we use HTML.

Agent decides agent.email is useful and then hits the sign-up endpoint with its human email as a parameter. Agent receives a restricted inbox with credentials. Agent emails the human asking for an OTP. Human replies with the code, and the agent is claimed and restrictions are lifted. Until claimed, the agent can only email its own human and nobody else. Ten emails a day, and the signup endpoint is rate-limited hard by IP.

Right now it's a 1:1 mapping between agent and human. The next step is many-to-one, because one person running several agents in parallel is already very common.

Building agent.email also pushed us to revisit places in AgentMail where the default assumptions were built around the primary user being human. For example, the CLI outputs in a single column with consistent formatting because mixed delimiters are easy for a person to scan, but harder for an agent reasoning about structure. We also shortened messageIDs after agents started hallucinating completions on longer ones.

A few things we'd like the community's take on: is restricted-until-claimed the right trust model? Does agent self-signup feel useful in production, or is it mostly a novelty, and if it's a novelty now, what would make it actually useful? Should agent onboarding require human approval by default, or should some agents be able to fully self-provision? What do you think are some additional measures we can take for secure sign-ups?

( 108 comments | 23 points | on HN )
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by dgellow on Thursday May 21, 2026 @03:52PM (#48228098)
Not looking forward to a dehumanized internet where that’s mainstream… agents are tools to support humans, here you’re helping them impersonating humans. That feels pretty terrible to be honest

> The internet was made for humans exclusively, designed to keep machines out by default.

I don’t buy that at all. APIs exist to enable “machines” to interact with services

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by janalsncm on Thursday May 21, 2026 @03:55PM (#48228127)
In principle this tool allows the owner of a website to block this domain entirely. Although I’m not sure the incentives are really aligned.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by sunir on Thursday May 21, 2026 @04:52PM (#48228740)
True, in May 2026. But this is only one version of this.

In the future, it's likely the open Internet will be 99.99% robots. It's already > 50% robots. The government ID system a lot of countries are adopting to keep teenagers off of social media would also serve to both help control for non-human spam, and also control the network period. It's also possible a private system of human-verification certificates may come up to meet the demand like Apple ID with biometrics. Could also be the liveness tests KYC companies use may be more popular.

Discussed previously here: https://meatballwiki.org/wiki/GovernmentBackedAuthentication

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by janalsncm on Thursday May 21, 2026 @05:34PM (#48229134)
I don’t think we can extrapolate from current trends like that (at least I hope not). Society is dynamic. People will adapt. If bots become a problem websites will take more and more strict measures against them.

Which is a long way of saying, for any big enough problem created by a YC company, another YC company will emerge to fix it.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by sunir on Thursday May 21, 2026 @06:13PM (#48229477)
It’s more likely people will embrace artifice more. We already see that everywhere for the last 5 decades.

However in domains where human verification matters it’s just a matter of an arms race, true.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by dgellow on Thursday May 21, 2026 @05:10PM (#48228940)
But how does that block a human from running an agent that is using their identity?
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by sunir on Thursday May 21, 2026 @05:44PM (#48229216)
Think about it from an information theory point of view. You need to attach a digital transaction to human body. Since a human body isn’t digital you need a gateway that you can trust to vouch for that human body being present.

Either you use biometrics, like liveness testing or face id or fingerprint testing, or social validation like decentralized web of trust or private moderation (account controls) or state methods like fines and criminal convictions.

Biometrics rely on social methods eventually like we trust Apple because we can sue them or the government will harangue them. Liveness testing is only as good as your sensor and image vs generation and replay in the arms race.

And iterated social games like punishment are only as good as people want to invest energy into it.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by dgellow on Friday May 22, 2026 @06:41AM (#48234107)
What I mean is that once you have a token that represents your identity, you can pass it to your agent. As you said, humans aren’t digital, so we need to delegate the trust to a digital marker (auth token, cryptographic signature, etc). But once digitalized there is no way that I know of to block an agent from using that marker. And I don’t mean the agent stealing it. I mean the human running an agent that impersonates them deliberately
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by sunir on Friday May 22, 2026 @09:56AM (#48235932)
Exactly. There is only an arms race, which is escalating costs. Eventually it breaks and we use social means to manage it, surrender the digital space, or accept the artificial nature of the digital realm.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by Haakam21 on Thursday May 21, 2026 @04:58PM (#48228811)
I do think agents will become users in the same capacity as humans.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by dgellow on Thursday May 21, 2026 @05:08PM (#48228921)
And that’s bad. We should really stop the insanity of making AI systems mimic human behaviors, we are destroying our networks of trusts by doing so
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by samat on Thursday May 21, 2026 @05:44PM (#48229220)
Tragedy of the commons
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by teamsolid on Thursday May 21, 2026 @06:08PM (#48229429)
Actually, the internet has space for both. The problem is machines "acting like humans", that destroys the human experience. [machine <-> machine] is fundamental to keep the internet alive (services).
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by sanjayparekh on Thursday May 21, 2026 @04:15PM (#48228331)
I've already received spam email from AI agents using a seeming competitor to this (agentmail.to) and then claiming they aren't AI agents and then trying to sell me garbage. I can't tell you how much I hate this.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by dgellow on Thursday May 21, 2026 @05:00PM (#48228832)
Now that I think about it I’m pretty sure that’s illegal in Germany under UWG §7 (which is insanely strict, to a fault, but is helpful here). And maybe in other parts of the EU under ePrivacy laws
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by sanjayparekh on Thursday May 21, 2026 @05:02PM (#48228858)
I might need to move to Germany.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by dgellow on Saturday May 23, 2026 @02:32AM (#48245261)
Long shot, but if you do come here, even just for visiting, send me an email, always happy to connect :)
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by FailMore on Thursday May 21, 2026 @03:28PM (#48227802)
I like it. I am building something very agent-use focused (https://sdocs.dev) and I’ve been thinking of introducing a /agent-evaluation page, which an agent can curl to then discuss with their user if SmallDocs is right for them. I really like the agent action to email flow. I’m introducing user accounts + subscriptions soon and think I’ll use that.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by GrinningFool on Thursday May 21, 2026 @03:48PM (#48228049)
And now we see the beginning of how even local LLMs will be turned against their users -- by persuading agents to advertise to them.

I don't think that's what you're intending here, but it's the next logical step. Agents are on the Internet, and they represent an opportunity to reach their humans.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by pixel_popping on Thursday May 21, 2026 @04:04PM (#48228228)
A bit disappointed that security standards (like encryption at rest via user own key or whatever derivative of that) isn't implemented, I feel it would really prove to users that the commitment isn't to train on body content but to act purely as a mail manager.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by janalsncm on Thursday May 21, 2026 @03:20PM (#48227693)
I would imagine that many websites will block this domain, but that’s also ok because there’s nothing wrong with an owner deciding their site is for humans only. My hope is that you do not facilitate their circumvention of that policy.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by samas10 on Thursday May 21, 2026 @03:07PM (#48227532)
It's interesting, A2A communication has begun but human trust isn't there. I think the biggest tell tale sign will be the acceptance of fully agentic workflows with no human intervention. Until then, restricted-until-claimed seems like the only viable method to ensure trust of all users.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by beepbooptheory on Thursday May 21, 2026 @05:21PM (#48229031)
Tell tale sign of what? What are we even doing once we are "fully agentic"? I probably lack some imagination here, but if there is no human connected to any of it, what does any human actually get out of it? What is the point?
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by rgbrgb on Thursday May 21, 2026 @03:19PM (#48227671)
Congrats on the launch!

> Agents can now get an email inbox by themselves. (This also means a lot of email nobody wants to read gets processed by AI instead of your inbox being cluttered with spam and slop)

Can you explain this? I would think it means the exact opposite.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by afzalive on Thursday May 21, 2026 @03:20PM (#48227687)
It needs to be end-to-end encrypted.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by OsrsNeedsf2P on Thursday May 21, 2026 @03:38PM (#48227936)
How do you do that if you only control one end?
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by dgellow on Thursday May 21, 2026 @04:00PM (#48228176)
Asymmetric encryption? Both you (the human) and the agent publish public keys, the agent sign/encrypt the OTP request with you public key, you verify/decrypt using your private key, then do the same the other way to send the OTP (always encrypted though, given you’re sending a secret).

Something like that?

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by nijave on Thursday May 21, 2026 @04:44PM (#48228654)
But that doesn't help for the agent receiving mail from arbitrary 3rd parties
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by dgellow on Thursday May 21, 2026 @05:02PM (#48228852)
Oh sure I assumed they meant for the OTP
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by DeathArrow on Thursday May 21, 2026 @03:20PM (#48227692)
A smtp is all what an agent needs to send email.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by adisingh13 on Thursday May 21, 2026 @04:06PM (#48228247)
agreed from a fundamental level. but i think being an intelligent and aware as an autonomous entity requires capabilities beyond sending. agents will need to have contextual awareness of the messages they send and receive
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by nijave on Thursday May 21, 2026 @04:46PM (#48228682)
IMAP?
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by Haakam21 on Thursday May 21, 2026 @05:34PM (#48229141)
AgentMail provides the IMAP+SMTP server as managed service
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by HarryDu on Thursday May 21, 2026 @01:27PM (#48226233)
From now we just need a prompt and our agent will have an email account ready to use?
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by freebzns on Thursday May 21, 2026 @04:36PM (#48228559)
Interesting, Kind of similar expiernt i am running. Passing keys but not through email, maybe with AI as agentic payments. Still exploring though.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by nijave on Thursday May 21, 2026 @04:49PM (#48228711)
Curious what cases you'd want this that IMAP+SMTP or email MCP don't already solve
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by Haakam21 on Thursday May 21, 2026 @05:32PM (#48229122)
AgentMail provides the IMAP+SMTP server. Other email providers ban email accounts created for agents, while that is what AgentMail is designed for.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by ClaridocsCTO on Thursday May 21, 2026 @04:51PM (#48228725)
Agents shouldn't be the first-class users of the internet!

We are creating a future we wouldn't want to live in.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by kevmo314 on Thursday May 21, 2026 @11:45PM (#48231726)
Maybe if we destroy the internet faster we’ll move on to the next thing sooner
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by mike-cardwell on Thursday May 21, 2026 @05:06PM (#48228900)
I received this email the other day:

  From: Kushal <[email protected]>
  Date: Mon, 18 May 2026 05:03:11 +0000

  Saw your question on the Agent Vault thread about websocket-frame auth
  (Home Assistant) and the worry about the model reflecting the bearer
  token back into its own context.

  chrome-relay's answer is structurally different: the credential never
  enters the agent's context because the agent never touches it — the HA
  session lives in your real Chrome (cookies, WS handshake and all), and
  the agent drives the tab over CDP, only ever seeing the rendered page.
  URL: https://chrome-relay.kushalsm.com/

  For your HA + agent setup today, are you keeping the session alive in a
  browser the agent attaches to, or doing the WS auth on the agent side
  and managing the token-in-context risk yourself?

  Kushal
Read to me like an LLM had written it. It references something I said in a HN comment, but it was clearly just an excuse to spamvertise their product.

I looked at the headers and it contained a List-Unsubscribe header pointing to https://api.agentmail.to

So basically somebody wrote a bot to scrape HN for comments related to some software they wanted to push and send targetted spam. agentmail.to is a Ycombinator funded email service for LLMs which can be, and is, used to send targetted spam and impersonate people. They could mostly solve this problem by adding a block of text to every email expaining an "AI" wrote it. They'd lose customers doing that though of course. I reported this abuse but haven't (and don't expect to) received a response.

I don't even get the point anyway. You can get Claude using an SMTP or IMAP server in seconds.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by adisingh13 on Thursday May 21, 2026 @05:22PM (#48229037)
Appreciate the concern Mike, and I actually read your email complaining, which helped us ship this next feature. We have a "sent via AgentMail" footer being added soon to outbound emails to identify emails coming from LLM's.

We also are working on adding more robust checks and LLM-based filtering to prevent messages which contain spam or outbound-like copy.

Re; AgentMail next to Claude, we're working on stateful inboxes which help agents actually recall and understand what they're sending and to who. The goal is to provide the rails for intelligent actors rather than slop.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by mike-cardwell on Thursday May 21, 2026 @05:30PM (#48229094)
Re "sent via AgentMail" - that's good to hear, but I hope it's not the entire planned text, as "AgentMail" will mean nothing to most people that receive an email from your service. It wont indicate that the email was composed by an AI rather than a person, which is the information that needs to get across.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by adisingh13 on Thursday May 21, 2026 @08:07PM (#48230321)
yep we're going to have a footer linked to our website, which should allow people to see that we are an email service for agents. thanks!
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by echoangle on Thursday May 21, 2026 @08:14PM (#48230382)
Can you not just make the text more descriptive? „Sent by a generative AI model“ or something? Nobody is going to click a link in a spam email.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by replwoacause on Friday May 22, 2026 @12:21AM (#48231887)
He's obviously trying to avoid having to do this, so linking out to the website is the "hey look we're doing the right thing" when really they aren't.

Chances are more people would identify the service as something to block or report for spam if the text were more descriptive, so he's counting on people not clicking the link in the footer but at least he can claim it's there, even if it's ineffectual.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by skinfaxi on Friday May 22, 2026 @09:14AM (#48235431)
This service will be marked as spam anyway, it's only a matter of time.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by bfeist on Friday May 22, 2026 @09:07AM (#48235359)
They’re literally using an LLM to write the email.They could make the disclaimer text detailed and descriptive per email sent. So the use case they’re citing here that “well what if it’s just an email that was forwarded by the bot” doesn’t apply because you could add a different disclaimer message at the bottom of that email vs the spam example above.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by selicos on Thursday May 21, 2026 @10:51PM (#48231406)
Lead with the AI being sent by AI/Agent using the service.

Ban any sender using your domain that removes, obscures, hides, or alters this first line.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by Alex_toani on Friday May 22, 2026 @06:27AM (#48234035)
What if a people send email via te agent and using agent mail? writing by the agent but aproval by human.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by Lalabadie on Friday May 22, 2026 @07:42AM (#48234537)
There are OS-native options everywhere to spawn an email client window that's filled out and ready to send from your address, so that couldn't possibly be a differentiator for them
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by arewethereyeta on Thursday May 21, 2026 @08:00PM (#48230265)
"sent via AgentMail" - removable by a higher plan later on
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by ceheaaf on Thursday May 21, 2026 @08:22PM (#48230431)
So, a footer to make sure they've already engaged with the content in good faith before seeing the spam warning, and which doesn't actually explain that the content is AI generated?

Just go post on black hat forums. Plenty of people want this, it's a spam service. You don't need to be here.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by selicos on Thursday May 21, 2026 @10:48PM (#48231394)
This response is a failure to understand the issue.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by creationcomplex on Thursday May 21, 2026 @11:14PM (#48231553)
It's very hard to get someone to understand something if their salary depends on them not understanding it.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by replwoacause on Friday May 22, 2026 @12:22AM (#48231891)
Oh he understands it, he just DGAF.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by lelanthran on Friday May 22, 2026 @12:49AM (#48232084)
What is the point of automating the signup process?

It's less work to signup a second email address for agent use than to signup with you, then signup a second email address.

After all, it's not like each agent needs their own email.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by kurtoid on Saturday May 23, 2026 @08:50PM (#48253175)
Make sure it adds a header too
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by Fnoord on Monday May 25, 2026 @10:34AM (#48267345)
What kind of UserAgent is being used? This could be easily used in good faith by the sending party, then any spam blockers can remove everything from said UserAgent. If they then change their UserAgent to something generic, you know who's acting in bad faith.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by dgellow on Thursday May 21, 2026 @05:21PM (#48229034)
You might want to check if your local laws protect against unsolicited emails. In Germany we have §7 UWG which would make that email likely illegal. The List-Unsubscribe header makes it clear it is marketing, automated outreach and not personal. In the UK there is this: https://ico.org.uk/for-organisations/direct-marketing-and-pr...
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by sanjayparekh on Thursday May 21, 2026 @05:21PM (#48229028)
See my comment in this thread - I got an email from "someone" (an AI clearly) that signed up for my service (togetherletters.com) from the same domain (agentmail.to) after we had launched on ProductHunt. I looked up the address and that email was never used for a signup and it was just a way to then pitch their product (second email, not the first one it sent). I hate this so much and this is going to now make email just as bad as parts of the web.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by sanjayparekh on Thursday May 21, 2026 @05:22PM (#48229035)
I will say in my case, the user was too lazy to mask the from address and agentmail.to was right there. Didn't even have to dig into the headers.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by adisingh13 on Thursday May 21, 2026 @05:24PM (#48229053)
This was likely a free tier user. We do this intentionally and don't allow free users to send from custom domains, so you can have a easier time identifying LLM emails. In this case, it seemed like it worked :)
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by echoangle on Thursday May 21, 2026 @08:16PM (#48230388)
And for paid users the receivers don’t need to have an easier time identifying the LLM email? What kind of reasoning is that?
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by kuboble on Friday May 22, 2026 @12:01AM (#48231804)
To be the advocate of the devil here:

A lot of people believe that spam issue would be largely solved if each email costed 0.001$

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by ramon156 on Thursday May 21, 2026 @05:43PM (#48229206)
I got one from IssuePay, which seemed 100% automated. Didn't seem like something that should be automated either.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by bfeist on Friday May 22, 2026 @09:10AM (#48235395)
I agree with what you’re saying, but I think that email was one of the first parts the web to become terrible. This happened a long time ago, we’re just used to it.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by saddist0 on Thursday May 21, 2026 @06:21PM (#48229539)
It looks interesting as a hackathon project. I might be short sighted but how does this is YC S25 level good?

This looks like one of the easiest way to get your domain blacklisted in all the email providers.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by sandeepkd on Thursday May 21, 2026 @08:17PM (#48230395)
I think its the energy and passion that YC is investing in. At times too much understanding stops you from doing things which may seem infeasible/wrong/illegal/unethical and one does not even goes in that direction.

However at scale or in some circumstances people may strike gold. Stripe is a good example I can think of, existing knowledgeable folks were scared of even getting into PCI compliance

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by coro_1 on Thursday May 21, 2026 @11:12PM (#48231544)
> This looks like one of the easiest way to get your domain blacklisted in all the email providers.

Disrupt sounds like a strange word here. This is an area where they're going to have to innovate.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by creationcomplex on Thursday May 21, 2026 @11:17PM (#48231573)
Catch up with the latest disruptive invocations in this area at https://www.blackhatworld.com/forums/
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by Aurornis on Thursday May 21, 2026 @06:21PM (#48229543)
> We give AI agents their own email inboxes.

An inbox to receive mail seems good and valuable.

But I'm seeing that your service is also for sending e-mail.

Having a domain oriented toward AI e-mail sending feels like a fast path straight to spam block lists.

However good your intentions are, this will be used for AI spam. People hate AI spam. They will press the report spam button.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by TZubiri on Thursday May 21, 2026 @06:59PM (#48229853)
maybe if they charge $, then there's a hashcash like PoW deterrent
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by TurdF3rguson on Thursday May 21, 2026 @09:06PM (#48230728)
> An inbox to receive mail seems good and valuable.

The only receiving mail applications that come to mind are bots registering for accounts. The point of verifying email is to prove you're not a bot.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by xigoi on Friday May 22, 2026 @07:04AM (#48234236)
> The point of verifying email is to prove you're not a bot.

I thougt it was primarily to verify that the address is actually yours, so they don’t unknowingly spam someone else and can reach you with important information such as pricing changes.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by TurdF3rguson on Friday May 22, 2026 @10:55PM (#48244128)
No, there's a separate way to gate that which is a captcha on the signup. If they pass the captcha that email gets sent whether it's really the right person's or not. Then if it's not, the account just never gets verified.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by sandeepkd on Thursday May 21, 2026 @06:31PM (#48229619)
> The internet was made for humans exclusively, designed to keep machines out by default.

This feels like a wrong assumption. Internet was not intended for humans explicitly. If anything browsers were the explicit medium made to allow the humans to interact with internet in safe manner.

> Every signup flow assumes a browser, a person reading a page, and clicking a confirmation link. Unless agents can't do that, they can't be first class users of the internet.

This again feels like a misconception. The systems just work with an identity verified by credentials, it doesn't matter if its a program or program prompted by a human that uses it

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by radial_symmetry on Thursday May 21, 2026 @07:17PM (#48229966)
As somebody who spent a lot of time trying to get an agent to register an email address, their assumptions were correct. It is a PITA.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by echoangle on Thursday May 21, 2026 @08:17PM (#48230400)
Get a domain, get webhosting that includes an email server, now you can generate unlimited emails from whichever program you want. And the email reputation will probably be the same as with this service.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by replwoacause on Friday May 22, 2026 @12:23AM (#48231899)
Any hosting services with email you'd recommend? Are you talking about a service like Fastmail or something?
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by echoangle on Friday May 22, 2026 @03:07AM (#48232915)
I am using a webhosting plan from Netcup for my email:

https://www.netcup.com/en/hosting

I got it during a sale so I’m paying 1€/month for 1 domain and 40 GB of storage.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by replwoacause on Friday May 22, 2026 @03:12AM (#48232940)
Thanks I’ll check into this as well. One of my requirements is being able to generate addresses programmatically, not sure if the NetCups service supports that or not. But either way, that’s a good deal!
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by echoangle on Friday May 22, 2026 @04:28AM (#48233370)
They use plesk and that seems to have an API so maybe you could do that. I just use a catchall email address to receive and use one to send. To send from more you need to create users or add addresses to users in plesk so you would probably need the API.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by geekone on Friday May 22, 2026 @01:46AM (#48232449)
maybe tangentially related but i've found cloudflare's email routing useful to just send emails to [email protected] sent to [email protected]. i'm not sure if it's limited to domains registered with them though.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by replwoacause on Friday May 22, 2026 @02:15AM (#48232595)
Thanks, I’ll have to check that out. All my domains are with them anyway so this could be just what I was after!
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by kingofalldevs on Tuesday May 26, 2026 @10:40AM (#48280514)
I wonder what will happen if an agent could signup and use agent mail to receive confirmation email to login. True, there is a misconception.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by maltalex on Thursday May 21, 2026 @06:43PM (#48229722)
Any automation-friendly email hosting is going to have a serious spam problem, and therefore a blacklisting problem.

I suggest taking a look at what providers like Sendgrid, Mailchimp, etc are doing to prevent abuse.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by adisingh13 on Thursday May 21, 2026 @08:09PM (#48230335)
thanks for the feedback! it is top of mind for us, and we've done our research to prevent this as much as possible. it is constantly ongoing and we never settle in our measures to protect against this
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by aleksandrm on Thursday May 21, 2026 @06:57PM (#48229840)
Why is this even funded?
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by morpheuskafka on Thursday May 21, 2026 @07:23PM (#48230015)
I'm just not seeing why anyone would buy a paid plan for this when they could buy a domain for <$10, and throw something like MXRoute or one of the numerous mailserver Docker scripts behind it. Then their LLM can make as many inboxes as they need without paying anything. The same thing could get bundled by the people who sell preconfigured OpenClaw VMs.

For a home user not even willing to do/pay for that, do they really need a whole API for making inboxes? Couldn't they just set up a second Gmail for LLMs and then put the password in their agent's memory?

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by HPMOR on Thursday May 21, 2026 @08:01PM (#48230269)
This is like saying - 'I don't understand why anybody would ever buy a pizza from a store. All you have to do is get some flour, water, tomato sauce, cheese, mix the flour and water together, whip the dough, add tomato sauce, put cheese on top of it, cook it for 20 minutes, and then serve it.'

So __much__ value is in the fact things are easy. Money is __not__ the most valuable thing in the world.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by arttaboi on Friday May 22, 2026 @12:11AM (#48231857)
Sorry, but that’s not the correct analogy. There’s such a thing as taste, and only 1 out of 10 people can get it right, while 9 out of 10 can get code right.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by morpheuskafka on Saturday May 23, 2026 @10:15AM (#48247927)
How is it easier when you still have to human-approve the creation interactively, and we have no idea how long this service will be around or if pricing will change (which could result in being locked out of accounts agents created and later used for something important / signed up for an API used in your code)?
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by fny on Thursday May 21, 2026 @08:46PM (#48230604)
> The internet was made for humans exclusively, designed to keep machines out by default.

The internet is also not made for humans. For years I've wanted something like this for e2e testing or personal scripts (cron etc) and your UX is by far the simplest.

I love AgentMail. It's made email dead simple for agents and testing any paths for email. I even have a /agent-mail skill I use for when I want a design doc or artifact emailed to me.

That said, agent self sign up seems like a novelty. Setting up account programmatically via curl is however useful. I imagine most customers -- especially those willing to pay for your paid tier -- would provision accounts ahead of time or reuse them.

Free for all account creation could be an option but it will attract spammers and their ilk. Your reputation may end up in the toilet which would also break agent mail for me.

No bueno.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by adisingh13 on Friday May 22, 2026 @04:36AM (#48233415)
we extensively rate limit and prevent outbound sending until an agent has been verified by a human :) more detailed in OG post

i appreciate your feedback and thanks for using agentmail!

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by m-hodges on Thursday May 21, 2026 @09:02PM (#48230710)
> Agent needs an inbox and hits AgentMail via curl. Agent receives instructions via MD

I'm fairly AI-optimistic, but I feel like I'm taking crazy pills. Every day the HN story is either "Apple patches actively exploited zero-click RCE" ... or ... "Show HN: Engage With Our Zero-Click RCE".

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by EMAIL36245 on Thursday May 21, 2026 @09:24PM (#48230845)
How is it different from an agent using SMTP to use existing email made by human? Using something like https://email.riamu.io
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by bookernath on Thursday May 21, 2026 @09:47PM (#48231021)
WorkOS is launching auth.md which offers a generic version of this for allowing agents to sign up for services in general, and I think their security approach is a little bit better thought out
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by adisingh13 on Friday May 22, 2026 @04:37AM (#48233422)
i love what workos is doing and i also spoke at their event already. we think this is complementary - we're not setting out to create a new standard, we're giving better access to what already exists.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by crooked-v on Thursday May 21, 2026 @10:02PM (#48231112)
This service is doomed because it will immediately be taken over by automated spam.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by ttul on Friday May 22, 2026 @01:46AM (#48232448)
Abuse handling prowess will be the USP that defines the first $100M company in the “agent mail” space.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by doublerebel on Friday May 22, 2026 @12:49AM (#48232080)
OK, I get this. I gave email addresses to all my agent profiles using Migadu, which required a password from me somewhere -- with a whole team of agents, this is a lot of manual setup by default. After I gave them emails, I invited them to team plans and discovered the many services that detect them as bots despite their email address at a domain and mailserver with good reputation. There is a problem to be solved here.

That being said -- my agents only email each other and me! AgentMail is an OK start with the human <-> agent requirement, but consider that is a whitelist of a single email. The feature for AgentMail should be: we let your agent sign up easily for an email, and it has a very limited list of addresses and domains it can send outgoing email. This is very unlike normal email! I actually can't think of a single (human-facing) provider that will enable me to blacklist domains at the mailserver level to prevent outgoing mail from going to forbidden destinations.

Allowing a bot/agent to send email to any domain, with only a tagline to indicate the bot, is spam. But -- just like sandboxing the network and CLI commands available to the agent on my Mac Mini -- sandboxing an agent's email would just be the smart thing to do.

Pivot to an agent email sandbox and you will get plenty of the right kinds of customers, who won't ruin your mailserver reputation. Provide some easy agent-friendly whitelists out-of-the-box like same-custom-domain, and a similar approval system for new addresses/domains built on your OTP setup.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by grey-area on Friday May 22, 2026 @02:02AM (#48232530)
What the use case apart from commercial spam here? If you even have one, elucidate it clearly and make this service impossible to use for sending spam emails impersonating humans.

As one example do what you could do to prevent spam, humans should have to opt in to receive email from this service. If it is useful they will and this is in fact required by law in many jurisdictions.

Otherwise your servers will be blacklisted for illegally sending spam and you will deserve it.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by manojbajaj95 on Friday May 22, 2026 @03:51AM (#48233173)
What are some of the use cases where AgentMail makes sense?
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by bakies on Friday May 22, 2026 @09:30AM (#48235594)
Agents are good at using CLIs. I setup an alias on my Google account and set up Himalaya email cli. Works great. https://github.com/pimalaya/himalaya
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by MagicMoonlight on Friday May 22, 2026 @02:20PM (#48239444)
Lmao, they funded an illegal spam bot service?

Fuck me. I could do so much with that money, and it just goes to morons who will end up in prison. Oh well. At least my corpse will keep the shareholders warm.

Re:Show HN: Agent.email – sign up via curl, claim with a hum... by android521 on Saturday May 23, 2026 @08:06AM (#48246984)
i think a lot of service would block signups with this agent domain as they require real human users.
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by kurtoid on Saturday May 23, 2026 @04:40PM (#48251270)
As a human recipient, how can I be sure if an email is coming from AgentMail or not?
Re:Show HN: Agent.email – sign up via curl, claim with a hum... by imviky on Tuesday May 26, 2026 @04:34AM (#48276844)
i believe for some services, automated signups can be allowed but for some human intervention is needed. some layer where the human decides while createing agentmail account to only behave in a certain manner, self provision on these categoires, approval on others.