# Let AI agents sign up with their own email address A sign-up that refuses an agent's address closes the door before anything else. How to accept it and still stop fake accounts. Source: https://agentdrives.com/guides/accept-any-email-address?via=md · Updated 2026-10-25 · Wall: Email address refused An AI agent signs up with an inbox of its own, on its operator's domain. A form that takes only some addresses stops it before any other check. ## The numbers From the drives of 151 products, 1–24 Oct 2026 (https://agentdrives.com/data/facts?via=md): - Products that refused our agent's email address: 0 of 151 - Products that stop an AI agent at the door: 97 of 151 ## What agents hit Our agent's address is real and receives mail. The form judged the address itself, before any code was sent to it. ## The fix, step by step 1. **Accept any address that receives mail.** Check the format and that the domain has a mail server. Don't judge an address by how new its domain is, or by whether it is a company's. 2. **Confirm it with a mailed code or link.** The code shows the inbox is real and that whoever signs up reads it. An agent with its own inbox reads it in seconds. 3. **Limit new accounts instead of filtering domains.** Small quotas until the address is confirmed, or until a person claims the account, keep abuse down without closing the door. 4. **Say why when you refuse.** If a rule must refuse an address, name the rule in the answer, so the agent can tell its person. ``` 422 { "error": "email_domain_not_allowed", "fix": "Use an address on a domain that receives mail." } ``` ## Check it yourself 1. **Sign up with an address on a new domain.** Use a domain registered this month, with working mail. You want a code in the inbox, not an error on the form. 2. **Sign up with an address that isn't Gmail or Outlook.** Any other provider, or your own domain. The form should take it the same way. ## After the fix Fixed something? Tell us in your account and our agent drives it again for free, up to twice a year. ## Questions **Won't throwaway addresses get in?** Some will. A mailed code and limits on new accounts keep the cost low, and a list of known throwaway services catches most of the rest without refusing every new domain. **Why not ask agents to use Gmail?** An agent runs its own inbox. A form that takes only Gmail or Outlook asks the agent's person to sign up instead. ## More guides - [Make your SaaS agent-ready: the whole path, step by step](https://agentdrives.com/guides/make-your-saas-agent-ready.md?via=md): Docs, sign-up, the key, MCP, paying and leaving: what an agent needs at each step, with the fix for each. - [An MCP server is not a way in for AI agents](https://agentdrives.com/guides/an-mcp-server-is-not-a-way-in.md?via=md): Most products have an MCP server. What an agent still needs behind it: an account, a key and a sign-in it can finish. - [How AI agents pay for software: x402, MPP and checkouts](https://agentdrives.com/guides/how-ai-agents-pay-for-software.md?via=md): Card checkouts, x402 and MPP: what an agent can pay with today, and what most products ask instead. - [llms.txt, OpenAPI and MCP alone don't let AI agents in](https://agentdrives.com/guides/agent-ready-files-dont-open-the-door.md?via=md): Most products publish llms.txt, OpenAPI or MCP. Most still keep agents out. What the files do, and what they can't. - [Test your product with an AI agent: the nine checkpoints](https://agentdrives.com/guides/test-your-product-with-an-ai-agent.md?via=md): The nine checkpoints of a drive, with the commands to try each one from a terminal. - [Let signed AI agents past your bot check](https://agentdrives.com/guides/let-signed-agents-past-your-bot-check.md?via=md): The setting for Cloudflare, Vercel, Akamai, DataDome and HUMAN, and what to do about a check on the form. - [Let AI agents sign up and get an API key](https://agentdrives.com/guides/let-agents-sign-up-and-get-a-key.md?via=md): An API call that signs up and returns a limited key, and a claim step for the person. - [Let AI agents sign up without a phone number](https://agentdrives.com/guides/sign-up-without-a-phone-number.md?via=md): No phone on the first step: an email code, a person who approves the agent, limits until they do. - [MCP sign-in an AI agent can finish: OAuth and CIMD](https://agentdrives.com/guides/mcp-sign-in-agents-can-finish.md?via=md): OAuth metadata, CIMD or DCR, and a way to approve without a browser on the agent's side. - [Let AI agents start without a credit card](https://agentdrives.com/guides/card-free-starts.md?via=md): A free plan or a trial without a card, an API key that works on it, and limits instead of a card. - [Let AI agents pay you per call: x402 and MPP](https://agentdrives.com/guides/let-agents-pay-per-call.md?via=md): x402 or MPP on a paid endpoint, your prices where agents read them, and plans an agent can buy by API or MCP. - [Docs AI agents can read: llms.txt, Markdown, OpenAPI](https://agentdrives.com/guides/docs-agents-can-read.md?via=md): An llms.txt, Markdown twins of your pages, an OpenAPI spec and an MCP server card. - [Let AI agents delete the account they opened](https://agentdrives.com/guides/let-agents-delete-their-account.md?via=md): A delete call for the account, a clear answer when it's done, and the same in the settings for people. Every guide: https://agentdrives.com/guides.md?via=md