Inbox Architecture & Technical Specs

AI spam detection, Gmail-like search, rules engine, and email drafting.

1. AI-Powered Spam Detection & Drafting

Score Range	Label	Action
0-30	safe	Deliver to inbox
31-70	suspicious	Deliver with warning banner
71-100	spam	Route to spam folder

2. Gmail-Like Search

Operator	Description	Example
`from:`	Sender email contains	`from:boss@company.com`
`to:`	Recipient email contains	`to:support@company.com`
`subject:`	Subject contains	`subject:invoice`
`has:attachment`	Has attachments	`has:attachment`
`is:starred`	Starred conversations	`is:starred`
`is:unread`	Unread conversations	`is:unread`
`is:pinned`	Pinned conversations	`is:pinned`
`is:muted`	Muted conversations	`is:muted`
`before:`	Before date	`before:2026-04-01`
`after:`	After date	`after:2026-03-01`
`label:`	Has tag/label	`label:finance`
`in:sent`	In sent folder	`in:sent`
`in:drafts`	In drafts folder	`in:drafts`
`in:archive`	In archive	`in:archive`
`in:trash`	In trash	`in:trash`
Query	What it matches
----------------------------------------	---------------------------------------------------
`from:boss@company.com`	Messages from that sender
`subject:invoice has:attachment`	Invoices with attachments
`is:unread from:client after:2026-04-01`	Unread messages from "client," sent after April 1st
`quarterly report is:starred`	Starred conversations matching "quarterly report"

3. Smart Rules Engine

Operator	Use Case	Example
`contains`	General match	from contains "@acme.com"
`equals`	Exact match	subject equals "Invoice"
`starts_with`	Prefix	subject starts_with "RE:"
`ends_with`	Suffix	from ends_with "@vendor.com"
`not_contains`	Exclude	body not_contains "unsubscribe"
Action	Effect
----------------	-------------------------------
`move_to_folder`	Files the message into a folder
`mark_read`	Marks the message read
`star`	Stars the conversation
`delete`	Deletes the message
`forward_to`	Forwards to another address
Rule Name	Conditions	Actions	Priority
--------------	------------------------------	------------------------	--------
VIP Customer	from contains "enterprise.com"	star, move_to_folder:VIP	1
Invoice Filing	subject contains "invoice"	move_to_folder:Finance	2
Spam Suspect	from contains "noreply"	delete	1

4. Outbound Delivery

Outgoing mail goes through a queue that renders templates, tracks delivery, and retries on transient failure.

Sending an email (API):

bash POST /inbox/messages/send { "accountId": "acct-xxx", "to": ["client@company.com"], "subject": "Meeting Request", "body": "Hi,\n\nI would like to schedule a meeting to discuss the quarterly results." }

Response:

json { "data": { "id": "msg-xxx", "direction": "outbound", "subject": "Meeting Request", "folder": "DRAFTS" } }

The message is queued for delivery and its status updates to sent once the outbound worker dispatches it. Passing a future scheduledFor timestamp holds the send until that time instead of dispatching immediately.

Templates: stored with {{variable}} placeholders (e.g. {{customerName}}, {{orderId}}) that get filled in at send time.

5. Conversation Threading

Messages are grouped into conversations by thread, ordered oldest-to-newest, with participant tracking and status kept in sync across the whole thread.

Get a conversation with its messages (API):

bash GET /inbox/threads/{conversationId}

Response:

json { "id": "conv-xxx", "subject": "Q2 Project Update", "status": "open", "messages": [ { "id": "msg-001", "from": { "name": "Client", "email": "client@acme.com" }, "subject": "Q2 Project Update", "textBody": "Hi,\n\nHere are the updates for Q2...", "attachments": [], "createdAt": "2026-05-10T14:00:00Z" } ] }

A conversation carries subject, participants, tags, priority (low / medium / high), status (open / closed / snoozed / archived / trash / sent / draft), an assignee, and read/star/pin/mute flags — everything a shared-inbox team needs to coordinate without stepping on each other.

Composes with the rest of the OS

Notifications