Email deliverability 101
Authentication, reputation, subdomain split, warmup, and complaints—agents obey the same rules as every other sender.
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Giving an agent a mailbox does not exempt it from deliverability physics. Filters do not care that the sender is a Neuro OS role. They care about authentication, reputation, content patterns, and how recipients complain. This is the short course.
Authenticate the domain
Publish SPF, DKIM, and DMARC for every domain and subdomain that sends. Alignment failures look like spoofing. Start DMARC in monitoring, then enforce when reports look clean. Agents that send through Agent Inbox still inherit whatever domain you attach—treat that domain as production infrastructure.
Reputation is earned slowly
New domains and IPs need warmup: low volume, engaged recipients, tight lists. Sudden spikes look abusive. Separate streams that behave differently. Billing mail and recruiting outreach should not share a subdomain; one complaint cohort should not sink the other.
Subdomain split
| Stream | Example | Notes |
|---|---|---|
| Transactional | billing.example.com |
High trust, low volume variance |
| Support agents | support.example.com |
Two-way, human Ask on send |
| Outreach | hello.example.com |
Strict lists, easy to quarantine |
Multi-tenant products must also decide whether tenants share reputation. Data isolation is not reputation isolation—multi-tenant email.
Complaints, bounces, lists
Honor unsubscribes. Remove hard bounces. Investigate complaint spikes as incidents. Allow and block lists on the agent reduce accidental mail to sinkholes. Do not buy lists. Do not let a model invent CC recipients outside policy.
Agents make the same mistakes faster
A loop that auto-sends without Ask can burn reputation before a human notices. Neuro OS defaults outbound to Ask for this reason. Rate-limit roles. Cap burst size. Log every approved send with thread id and approver.
Content and identity
Misleading subjects, malformed MIME, and spoofed display names hurt trust. Keep reply identity stable so threads continue—email threading. Use email as identity deliberately—email as identity.
Operational integrations
When 1C, Bitrix, or amoCRM forward into an agent inbox, the outbound reply still leaves through your authenticated domain. Forwarding does not bypass DMARC. Design the From and Return-Path with the same care you give human mailrooms.
Deliverability is not a marketing afterthought for agents. It is part of the channel architecture. Authenticate, split risk, warm carefully, gate sends, and treat complaints as first-class signals.
Monitoring that agents can help with
Roles can draft digests of bounce rates, complaint rates, and DMARC aggregate highlights for a human owner. They should not auto-change DNS or blast apology campaigns without Ask. Use the agent to assemble evidence; keep domain control with people.
Instrument per-role send volume and error codes. A sudden climb in 5xx or spam folder placement is an incident, not a prompt tweak. Pause the role’s outbound allow list until the cause is clear.
Warmup for agent streams
New agent addresses often look like new product mail. Start with internal recipients and known customers who expect the role. Expand gradually. Keep content specific and requested. Avoid identical bodies across thousands of recipients—that pattern is how filters fingerprint automation, whether or not a model wrote the text.
Shared infrastructure myths
Sharing one authenticated domain across every tenant and every agent “to keep DNS simple” is a reliability choice with blast radius. Simplicity at DNS can become complexity at incident response. Prefer deliberate splits early, especially when one tenant’s outreach habits differ from another’s transactional traffic.
Agent Inbox gives each role a mailbox people can reply to, with forwarding into Neuro OS when a human must see the thread. Outbound mail defaults to Ask. Run the role on Neuro OS. To scope the first inbox, get started.