ComparisonUpdated October 29, 2026

Inbox Zero vs Command Mail: AI assistant or inbox for your agent

Inbox Zero brings its own AI assistant into your Gmail or Outlook account: it labels, archives and drafts replies by rules you write in plain English, from $18 per user per month billed annually.[1][4] Command Mail is a hosted inbox for all your addresses, and your own agent, such as Claude, ChatGPT or Codex, works in it with permissions per connection plus an autonomy level per mailbox.[14]

Both offer a hosted MCP server, so the real differences are who does the work, which mailboxes are covered and where the line before sending sits.[6][14] If you want an assistant that runs by itself inside Gmail or Outlook, or you want to host the software yourself, Inbox Zero is the closer match. If your agent already does the thinking and should work across addresses from any provider, with a server-side approval before a message goes out, Command Mail fits better.

This page is about Inbox Zero the product from Inbox Zero Inc., not the email method of the same name. Command Mail is our product. Everything about Inbox Zero comes from its pricing page, documentation, privacy policy and GitHub repository, retrieved on 2026-10-29; we have not tested Inbox Zero ourselves.[1][5][13] Statements about Command Mail's permissions and limits also rest on its app code at commit 0f7fe90.

As of: 2026-10-29

Updated: Fact-checked: About 11 min readAs Markdown

Contents
  1. What this comparison covers
  2. Inbox Zero and Command Mail at a glance
  3. What Inbox Zero does well
  4. Where Inbox Zero reaches its limits
  5. How Command Mail draws the line
  6. Example: client inquiries across a Gmail and a domain address
  7. When Inbox Zero is the better choice
  8. When Command Mail fits
  9. Who Command Mail is not for
  10. Switching and setup
  11. Further reading
  12. Frequently asked questions
  13. Sources

01What this comparison covers

Inbox Zero describes itself as an open-source AI email assistant for Gmail and Outlook.[18] When you sign up, you connect your mailbox and approve permissions so it can read and organize messages, create drafts and send mail.[3] Its default rules label messages that need an answer as To Reply with a draft waiting, sort everything else into categories and archive noisy ones such as marketing and cold email.[2] Around that sit bulk unsubscribe, analytics, calendar features, meeting briefs and chat from Slack, Microsoft Teams or Telegram.[2]

Command Mail starts from a different place. Your addresses arrive by forwarding, each through its own private inbound address, and your agent connects through a hosted MCP server, an official ChatGPT plugin, a Claude directory listing or Command Mail's CLI.[15][14] Command Mail itself sorts mail into categories, adds markers such as Invoice or Deadline, scores spam and phishing risk and prepares a morning brief.[15]

So the question this page answers is practical: do you want a ready-made assistant inside your existing mailbox, or an inbox in which an agent you already use gets clearly limited rights?

02Inbox Zero and Command Mail at a glance

QuestionInbox ZeroCommand Mail
Price (retrieved 2026-10-29)email app free; AI plans Starter $18, Plus $28, Professional $42 per user per month billed annually, or $20, $35, $50 monthly; 7-day trial[1]Free €0 (one mailbox, last 90 days, no sending); Pro €19/month for the first 100 paying Pro accounts while the subscription runs, otherwise €29/month (yearly €190 or €290); Team €39 per person per month[14]
Who does the workInbox Zero's own assistant, steered by rules in plain English; your own AI provider key is optional[4][10]the agents you connect, within the permissions you grant; Command Mail adds categories, markers, risk scores and the morning brief[14][15]
MailboxesGmail, Google Workspace, Outlook and Microsoft 365, connected directly; Plus includes two email accounts per user[2][1]any address by forwarding; one active mailbox on Free, up to ten on Pro[14]
Agent connectionhosted MCP server with OAuth, sign-in through Google or Microsoft; public API and CLI[5][6][20][21]hosted MCP server with OAuth, official ChatGPT plugin, Claude directory, CLI and local MCP[14]
Agent permissionsmcp:read; mcp:write for drafts and rules; mcp:send only when the client requests it; every MCP scope covers all linked inboxes[6]mail:read, mail:draft, mail:send-approved, mail:send per connection, with mail:read covering every mailbox in the account; autonomy read, suggest, rules or auto per mailbox[14]
Sending without a personenabled rules can send replies, send new email or forward[4]only with mail:send from a mailbox on auto, with a daily limit, at most 20 recipients and a send key per email[14]
Self-hostingyes, with Docker; AGPL-3.0 with additional terms[11][12]no self-hosted version described[15]
OperatorInbox Zero Inc., Delaware, USA[13]FYN Labs LLC, USA; attachments stored in Cloudflare's EU region[16]

03What Inbox Zero does well

Inbox Zero works where you already read mail. Labels, archived messages and drafts appear in Gmail or Outlook, and you keep reading and sending there as before.[2] You need no forwarding and no second inbox, and there is also a free email app of its own for the web, desktop and iPhone.[1]

The rules are flexible. A condition can be an AI instruction such as a request to set up a call, a static match on sender, recipient or subject, or both.[4] Actions include labeling, moving, archiving, drafting, forwarding, marking as spam, calling a webhook or creating a Todoist task, and supported actions can wait between one minute and 90 days.[4] Before you rely on a rule, the Test tab runs it against a message without applying anything, and History shows what matched; Fix lets you explain a wrong match so the rule is updated.[4][3]

Drafting is tunable. Draft confidence decides whether the assistant drafts for every email that needs a reply or only when it is sure, and writing style, personal instructions and a knowledge base shape the tone.[9] Auto-drafted replies are not sent automatically.[9] A sensitive-data setting can redact or block detected credentials and card numbers before content goes to an AI provider.[9]

You choose the model and the hosting. By default Inbox Zero covers AI costs, but you can enter your own key for Anthropic, OpenAI, Google, Azure OpenAI, Groq, Cerebras, OpenRouter or Vercel AI Gateway.[10] Self-hosting starts with two commands, npx @inbox-zero/cli setup and npx @inbox-zero/cli start, with Docker and Node.js 24 or later; the wizard walks you through your own Google or Microsoft OAuth app and AI provider.[11] The privacy policy says Inbox Zero does not allow its AI providers to train models on your data.[13]

For outside agents, the MCP server lets ChatGPT, Claude or Cursor search and read mail, create drafts, manage rules and read statistics.[5] You can disconnect one app or remove single permissions in Settings, and turning MCP off revokes every connection at once.[6] The repository is active, with more than 12,800 stars on the day we checked.[19]

04Where Inbox Zero reaches its limits

Inbox Zero covers Gmail and Outlook. Its documentation describes Google and Microsoft accounts and does not describe IMAP accounts or other providers.[2][3] A domain address hosted elsewhere is only in scope if its mail ends up in one of those mailboxes.

Rules act on your real mailbox, and they run automatically once enabled.[8] That includes outbound actions: the action list contains Send replies, Send email and Forward.[4] Inbox Zero itself advises starting with labels, archiving or marking as read and adding outbound actions only once you trust how a rule matches.[3] The documentation we read describes no daily limit or recipient cap for these actions. Deleted mail is harder to recover and depends on how Gmail or Outlook retain it.[8]

Sending through MCP is described in two ways. The Connect MCP guide says the assistant cannot send email and drafts stay in your mailbox.[5] The MCP reference and llms.txt add a separate mcp:send scope that is granted only when a client requests it.[6][18] In the current source code, the matching send_mail tool is visible only to the mail interface the client displays, not to the model, and its description says that interface asks the user to confirm recipients and content first.[7] In Inbox Zero's own chat, too, you review prepared messages and send them from a confirmation card.[17][8]

MCP permissions are not split by mailbox. Every MCP scope applies to all inboxes linked to your user, including ones you add later.[6] For scripts, the public API and its CLI use keys bound to one inbox, with selected scopes for statistics, rules and unsubscribing.[20][21] Connecting an assistant also needs a Google or Microsoft sign-in; sessions started with an email code cannot authorize MCP clients.[5]

The license matters if you self-host at work. The code is published under the AGPL-3.0 with additional terms: selling access to the software or offering it as a paid service needs written permission from Inbox Zero Inc., and organizations with five or more business users need an enterprise license.[12] Personal, educational and research use and organizations with fewer than five business users are exempt.[12]

05How Command Mail draws the line

Command Mail splits control into two layers. When you connect an agent, you choose its permissions: mail:read reads and sorts, mail:draft writes drafts and never sends, mail:send-approved sends exactly the draft revision a person approved, and mail:send sends without asking.[14] Every permission can be switched off when connecting, and sending without approval starts switched off.[14] On top of that, each mailbox has an autonomy level: read, suggest, rules or auto.[14]

An agent sends directly only from a mailbox on auto and only with mail:send. Each email then needs its own send key, a daily limit applies, 50 by default, and a message can have at most 20 recipients.[14][15] On suggest and rules, archiving, spam and deletion actions become suggestions and mail leaves only through approved drafts; on read, the agent changes no mail and sends nothing.[15]

Only a person in the browser can approve drafts, decide on suggestions and change autonomy.[15] In mailboxes on rules or auto, an agent can also switch on a rule itself. Agents do not write on their own to detected automated senders, mailing lists or no-reply addresses; detection relies on message signals such as RFC 3834 headers.[15]

Sorting actions by agents and rules and changes to rules appear in the activity log, where suggestions wait for your decision. Supported sorting actions can be undone; sent and permanently deleted mail cannot.[15]

Command Mail has limits too. Mail arrives by forwarding, so whatever the agent archives stays unchanged in the original mailbox; changes do not sync back.[15] Like Inbox Zero's scopes, mail:read covers every mailbox in the account; the per-mailbox autonomy level limits what an agent may change, not what it may read.[14] Sending is set up per sender address from Pro.[15] The operator is FYN Labs LLC in the US, the app runs on Cloudflare, and attachments are stored in Cloudflare's EU region.[16]

06Example: client inquiries across a Gmail and a domain address

Say you run a personal Gmail address and hello@ at your own domain with a host that is neither Google nor Microsoft, and you want replies to new client inquiries prepared every morning.

With Inbox Zero, you connect the Gmail account and write a rule such as: if the email is a new project inquiry, label it Inquiry and draft a reply.[4] With auto-drafting on, the draft waits in your Gmail drafts folder for you to read and send.[9] The domain address is covered only if its mail lands in a Google or Microsoft mailbox that Inbox Zero is connected to.[2]

With Command Mail, you forward both addresses into it; two active mailboxes need Pro.[14] Your agent, for example Claude Code on a schedule you set up in the agent, reads with mail:read and writes drafts with mail:draft.[14][15] You approve each draft in the app, and with mail:send-approved the agent then sends exactly the version you approved.[14]

The trade-off is clear in this example. Inbox Zero needs no agent of your own and stays inside Gmail; Command Mail needs an agent but treats every address the same way and holds outgoing mail until a person has approved it.[2][14]

07When Inbox Zero is the better choice

Choose Inbox Zero if you want an assistant that works by itself and you do not run an agent of your own. You describe in plain English what should happen with your mail, test the rules, and labels, archive and drafts then appear in Gmail or Outlook, where you already work.[4][2] Calendar-aware drafts, meeting briefs, follow-up reminders and chat from Slack, Teams or Telegram are part of the product; the pricing page lists the Slack integration and email digests from Plus.[2][9][1]

Inbox Zero is also the better choice if you want to run the software yourself or pick the AI model. You can self-host with Docker and your own OAuth apps, and in the hosted version you can bring your own provider key.[11][10] For individuals and organizations with fewer than five business users, the license exempts self-hosting from the enterprise requirement.[12] If you mainly want an empty inbox in Gmail with bulk unsubscribe and bulk archive, it covers that directly.[2]

08When Command Mail fits

Choose Command Mail if you already use Claude, ChatGPT, Codex or another agent and want it to work in your mail with permissions you can read on one page. With mail:send-approved, only the version you approved goes out, and direct agent sending carries a daily limit, a recipient cap, a send key per email and the block on detected automated senders.[14][15]

It also fits if your addresses come from different providers. Anything you can forward arrives in one inbox, whether it lives in Gmail, Outlook or with a domain host.[15] You connect your agent by URL, through the official ChatGPT plugin or the Claude directory listing, and you can start free with reading and drafts.[14]

09Who Command Mail is not for

If you want an assistant that sorts and drafts inside Gmail or Outlook without an agent of your own, Inbox Zero is the closer match.[2] Command Mail does not replace your existing account, and changes do not flow back to the original mailbox.[15]

If you need to host the software on your own servers, look at Inbox Zero: Command Mail is documented as a hosted service, and its documentation describes no self-hosted version.[15][16] Sending starts on Pro.[14]

10Switching and setup

To Inbox Zero: sign in at getinboxzero.com with Google or Microsoft, approve the requested permissions and complete the guided Assistant setup; test each rule before you add outbound actions.[3] To connect an agent, open Settings, then Account, then MCP, turn MCP on and copy the URL https://www.getinboxzero.com/mcp; in Claude Code the command is claude mcp add --transport http inbox-zero https://www.getinboxzero.com/mcp.[5] When the client asks for permissions, check whether it requests mcp:send.[6]

To Command Mail: connect each address in the app and set up forwarding at your current provider to the private inbound address Command Mail shows you.[15] Then connect your agent, in Claude Code with claude mcp add --transport http commandmail https://commandmail.app/mcp, or in ChatGPT through the plugin.[14] Start with mail:read and mail:draft only.

Running both is possible. Decide up front where sorting happens, because an archive in Command Mail does not reach Gmail or Outlook and Inbox Zero's labels do not reach Command Mail.[2][15]

11Further reading

You can start Command Mail for free and let your agent read and draft before it sends anything.

Frequently asked questions

Is Inbox Zero the product the same as the inbox zero method?

No. This page is about Inbox Zero from Inbox Zero Inc. at getinboxzero.com, an AI email assistant for Gmail and Outlook. The inbox zero method is a way of handling email that any tool can support, including Command Mail.

Is Inbox Zero open source?

Its code is public on GitHub under the AGPL-3.0 with additional terms from Inbox Zero Inc. Personal, educational and research use and organizations with fewer than five business users are exempt from those terms. Organizations with five or more business users need an enterprise license, and selling access to the software needs written permission.

Can Inbox Zero send email on its own?

Yes, if you set it up that way. Rules can include the actions Send replies, Send email and Forward, and enabled rules run automatically as mail arrives. Through MCP, the standard read and write scopes create drafts and never send. Sending needs the separate mcp:send scope, and in the source code that tool is meant for the mail interface the client displays, after the user confirms recipients and content.

Do I need my own AI agent for Command Mail?

Command Mail is built so that the agent you connect, such as Claude, ChatGPT or Codex, works in your mail with the permissions you grant. Without an agent, it still sorts mail into categories, adds markers such as Invoice or Deadline, scores spam and phishing risk and prepares a morning brief.

How much do Inbox Zero and Command Mail cost?

Inbox Zero's email app is free; its AI plans cost $18, $28 or $42 per user per month billed annually, or $20, $35 or $50 monthly, after a 7-day trial. Command Mail Free costs nothing and reads and drafts but does not send; Pro is €19 a month for the first 100 paying Pro accounts while the subscription runs, then €29.

Can I use Inbox Zero and Command Mail together?

Yes. Inbox Zero works in your Gmail or Outlook account, and you can additionally forward an address to Command Mail. You then have two separate states: what an agent archives in Command Mail stays where it was in Gmail or Outlook.

Sources

  1. Inbox Zero: Pricing getinboxzero.com, accessed
  2. Inbox Zero Docs: Introduction docs.getinboxzero.com, accessed
  3. Inbox Zero Docs: Getting Started docs.getinboxzero.com, accessed
  4. Inbox Zero Docs: AI Personal Assistant (rules, conditions, actions) docs.getinboxzero.com, accessed
  5. Inbox Zero Docs: Connect MCP docs.getinboxzero.com, accessed
  6. Inbox Zero Docs: MCP server (scopes, tools, discovery) docs.getinboxzero.com, accessed
  7. Inbox Zero source code: MCP tool definitions incl. send_mail (GitHub, commit 62087fe) github.com, accessed
  8. Inbox Zero Docs: Security, Permissions, and AI docs.getinboxzero.com, accessed
  9. Inbox Zero Docs: Assistant Settings docs.getinboxzero.com, accessed
  10. Inbox Zero Docs: Use Your Own AI API Key docs.getinboxzero.com, accessed
  11. Inbox Zero Docs: Self-hosting Quick Start docs.getinboxzero.com, accessed
  12. Inbox Zero: LICENSE (AGPL-3.0 with additional terms, GitHub) github.com, accessed
  13. Inbox Zero: Privacy Policy getinboxzero.com, accessed
  14. Command Mail: llms.txt (pricing, permissions, connection) commandmail.app, accessed
  15. Command Mail: documentation commandmail.app, accessed
  16. Command Mail: privacy, operator and hosting commandmail.app, accessed
  17. Inbox Zero Docs: AI Chat docs.getinboxzero.com, accessed
  18. Inbox Zero: llms.txt (agent and developer interfaces) getinboxzero.com, accessed
  19. Inbox Zero on GitHub (repository) github.com, accessed
  20. Inbox Zero Docs: API introduction (inbox-bound API keys and scopes) docs.getinboxzero.com, accessed
  21. Inbox Zero Docs: API CLI docs.getinboxzero.com, accessed
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