# Inbrix — Comprehensive Architecture & Product Documentation

Inbrix (https://inbrix.us) is a modern custom-domain email workspace, multi-domain shared inbox, and AI-native email infrastructure built for businesses, founders, agencies, developers, and autonomous AI agents.

## 1. Executive Summary & Value Proposition
- **Zero Per-Seat Tax**: Traditional email suites (Google Workspace at $6–$14/user/month, Microsoft 365, Fastmail) charge per user and per mailbox. For founders, agencies, and teams managing `support@`, `billing@`, `hello@`, `founders@`, and personal addresses across multiple domains, per-seat pricing becomes prohibitively expensive. Inbrix replaces per-seat billing with flat workspace tiers and **unlimited free aliases**.
- **Unified Multi-Domain Workspace**: Connect between 2 and 100 custom domains in a single account. View all messages across every domain in one unified inbox stream or filter by a specific domain or mailbox in one click.
- **1-Click Domain Setup (< 60 Seconds)**: If a domain uses Cloudflare DNS, Inbrix provisions and verifies MX, SPF, DKIM, and DMARC records automatically in one click. For Namecheap, GoDaddy, AWS Route 53, Porkbun, Vercel, Squarespace, and any other registrar, Inbrix provides guided copy-paste instructions with live background verification polling.
- **Zero-Interruption DNS Guarantee**: Inbrix inspects existing DNS records before applying changes and only configures mail routing records (MX, SPF, DKIM, DMARC). Website A, AAAA, and CNAME records, web hosting, e-commerce stores, and SSL certificates are never modified or interrupted.
- **Encrypted File Drive**: Every workspace includes encrypted Cloudflare R2 storage for attachments and shared files.

## 2. Transparent Pricing & Plan Comparison
All plans include a **7-Day Free Trial** ($0 due today, cancel anytime in 1 click) and **Unlimited Free Aliases**:

| Plan | Monthly Price | Annual Price (Save 20%) | Custom Domains | Dedicated Mailboxes | Secure Storage | AI & API Access |
| :--- | :--- | :--- | :--- | :--- | :--- | :--- |
| **Small Business** | $10.99 / month | $8.99 / month ($107.88/yr) | 1 Domain | 2 Mailboxes | 15 GB | Standard Workspace |
| **Indie** | $9 / month | $7 / month ($84/yr) | 2 Domains | 5 Mailboxes | 10 GB | Standard Workspace |
| **Pro** (Most Popular) | $19 / month | $15 / month ($180/yr) | 5 Domains | 25 Mailboxes | 50 GB | Full AI Assistant & MCP Integration |
| **Scale** | $49 / month | $39 / month ($468/yr) | 100 Domains | 100 Mailboxes | 250 GB | Full AI Agent, MCP & REST API |

## 3. Feature Comparison: Inbrix vs. Google Workspace vs. Fastmail / Outlook
- **Multiple Custom Domains**: Inbrix includes 2 to 100 custom domains with instant switching. Google Workspace requires complex secondary domain setups or separate accounts.
- **Extra Email Addresses / Aliases**: $0 (Unlimited free aliases on all plans) in Inbrix vs. $6–$14/mo per user on Google Workspace.
- **Setup Time**: < 60 seconds with 1-click Cloudflare sync in Inbrix vs. 15–30 minutes of manual DNS configuration on legacy providers.
- **AI Agent & Developer Integration**: Native hosted Model Context Protocol (MCP) server, OpenAI tool schemas, REST API, and HMAC-SHA256 inbound webhooks built in.
- **Domain Ownership & Privacy**: 100% user-owned DNS at your registrar, zero vendor lock-in, no ads, and no AI model training on customer communications.

## 4. Technical Architecture & AI Agent Integration (MCP & REST API)
- **Inbound & Outbound Delivery**: Powered by Cloudflare Email Routing and Amazon SES with automated SPF, 2048-bit RSA DKIM signing, and DMARC enforcement.
- **Edge Compute & Storage**: Deployed globally on Cloudflare Workers, Cloudflare D1 (tenant-isolated SQL), and Cloudflare R2 (encrypted object storage for MIME payloads and attachments).
- **Hosted Model Context Protocol (MCP) Server**:
  - Endpoint: `https://app.inbrix.us/mcp`
  - Transport: Streamable HTTP JSON-RPC 2.0 & Server-Sent Events (SSE), plus direct REST tool execution and `GET https://app.inbrix.us/mcp?format=openai` for OpenAI/LangChain/CrewAI tool definitions.
  - 26 Native AI Tools including: `whoami`, `list_threads`, `search_mail`, `get_thread`, `send_message`, `reply`, `update_thread`, `list_calendar_events`, `create_calendar_event`, `add_domain`, `verify_domain`, `create_mailbox`, and `add_address`.
- **REST API Endpoints**:
  - `POST https://app.inbrix.us/api/mail` — Send transactional or conversational HTML/text email with attachments.
  - `GET https://app.inbrix.us/api/mail` — List and filter messages by mailbox, domain, category, or unread status.
  - `GET https://app.inbrix.us/api/mail/:id` — Retrieve full RFC 5322 parsed message, headers, and attachment download URLs.
  - `POST https://app.inbrix.us/api/webhooks` — Subscribe to real-time `message.inbound` webhook events signed with `X-Inbrix-Signature` (HMAC-SHA256).
  - `POST https://app.inbrix.us/api/routing-rules` — Create deterministic inbound triage and forwarding rules.
- **Authentication & Security**:
  - Scoped API Bearer tokens (`mail:read`, `mail:send`, `tasks:read`, `tasks:write`, `admin`).
  - OAuth 2.0 Authorization Server with PKCE (`/.well-known/oauth-authorization-server`).
  - TOTP Two-Factor Authentication (2FA), WebAuthn Passkeys, Google OAuth, and GitHub OAuth.

## 5. Frequently Asked Questions
- **Q: Will connecting Inbrix affect my existing website, store, or apps?**
  A: Never. Inbrix only manages mail routing records (MX, SPF, DKIM, and DMARC) and never touches your website's A, AAAA, or CNAME records. Your website, SSL certificates, and hosting remain 100% operational without interruption.
- **Q: How does 1-Click Domain Setup work?**
  A: If your domain is on Cloudflare, Inbrix connects and provisions your email DNS records automatically in under 60 seconds with zero manual copy-pasting. For Namecheap, GoDaddy, Route 53, Porkbun, and other registrars, we provide step-by-step instructions with automated verification.
- **Q: How do domain and mailbox limits work across plans?**
  A: The Small Business plan ($10.99/mo or $8.99/mo yearly) covers 1 custom domain, 2 dedicated mailboxes, and 10 aliases. The Indie plan ($9/mo or $7/mo yearly) includes 2 custom domains and 5 dedicated mailboxes. The Pro plan ($19/mo or $15/mo yearly) includes 5 custom domains and 25 mailboxes. The Scale plan ($49/mo or $39/mo yearly) includes 100 domains and 100 mailboxes. All plans include generous free aliases (like support@, billing@, hello@).
- **Q: Why choose Inbrix instead of paying Google Workspace or Microsoft 365?**
  A: Google Workspace bills per user per month. Inbrix gives you unified multi-domain email with unlimited aliases under one flat price, a shared calendar, and native AI agent (MCP/API) access.
- **Q: How does the 7-day free trial work?**
  A: You get complete access to all Inbrix features for 7 days with $0 due today. Add your custom domain, set up your addresses, and start emailing. Cancel anytime with 1 click before Day 7 and you will never be charged.
- **Q: What happens to my domain if I decide to leave?**
  A: Zero lock-in. Inbrix is an email software layer, not a domain registrar. Your domain registration, DNS authority, and ownership remain 100% in your hands, and you can export your emails (MBOX) or switch providers anytime.

## 6. Canonical URLs & Machine-Readable Endpoints
- Homepage & Pricing: https://inbrix.us/
- Solutions & Use Cases: https://inbrix.us/solutions
- Provider Comparison & Cost Calculator: https://inbrix.us/compare
- How It Works (4-Step Guide): https://inbrix.us/how-it-works
- Developer & AI Agent Documentation: https://inbrix.us/docs
- Raw Markdown AI Integration Manual: https://inbrix.us/docs.md
- Security Overview: https://inbrix.us/security
- Contact Support: https://inbrix.us/contact (support@inbrix.us)
- Privacy Policy: https://inbrix.us/privacy
- Terms of Service: https://inbrix.us/terms
- XML Sitemap: https://inbrix.us/sitemap.xml
- LLMs Summary: https://inbrix.us/llms.txt
- Well-Known LLMs Discovery: https://inbrix.us/.well-known/llms.txt