Fluxmail vs AgentMail

AgentMail is an email provider built for agents. An API call creates a new inbox with its own address on agentmail.to or on a domain you verify, and the agent sends and receives from that identity. Its docs describe routing unrecognized addresses on a Google Workspace domain to AgentMail, but they do not describe connecting an existing Gmail or Outlook mailbox.

Fluxmail starts from the mailboxes you already use. It connects Gmail, Google Workspace, Microsoft 365, Outlook.com, and IMAP/SMTP accounts, so an agent can triage your inbox, draft replies in your threads, and send from your address. Fluxmail Cloud hosts the connection without storing messages or attachments. Self-hosted Fluxmail runs on your computer or server, so email never passes through a service Fluxmail runs.

AgentMail sends an event when a message arrives, is sent, is delivered, bounces, or draws a complaint. Webhooks need a public URL, and WebSockets deliver the same events over a persistent connection. Webhook payloads are capped at 1 MB, so for a larger message the app fetches the body through the API.

AgentMail's MCP server also publishes a new-mail event. In some ChatGPT chats, that lets an assistant act on an email soon after it arrives instead of checking on a schedule. The event carries only metadata, so the assistant reads the message with the get_message tool.

Fluxmail has no built-in inbound events. An agent or app checks for new mail over MCP or REST (or the CLI when self-hosted) when a person asks or on a schedule. That suits an assistant working in your inbox on request. An app that must react to every incoming message within seconds is a better fit for AgentMail.

AgentMail's server is at mcp.agentmail.to. Claude and ChatGPT sign in through the AgentMail console, Cursor and similar clients can send an API key in a header, and a stdio bridge covers clients that can't send headers. It has 47 tools, including inboxes, threads, messages, drafts, attachments, calendar events, allow and block lists, and app connections.

Fluxmail Cloud's server is at cloud.fluxmail.ai/mcp. Clients sign in with OAuth, and scripts can use an agent key. Its tools cover listing, reading, drafting, sending, forwarding, and organizing mail, and downloading attachments. A connection only sees the tools its permissions allow, so a read-only client never receives send_email.

Anyone can email an agent, so both products assume some messages will try to manipulate it. AgentMail's Agent Armor, in its Labs program, scans incoming mail and labels each message clear or review. In Hold mode, a message marked review sends no new-mail webhook or WebSocket event until a person releases it. Agents that list, search, or read over IMAP still see a held message unless they skip the held label. AgentMail also calls a clear verdict advisory, not a guarantee.

Fluxmail does not scan messages and has no recipient allowlist. Instead, you choose a permission preset when each client signs in. A Read only connection cannot send, forward, or delete. Read and write adds drafts, organizing, and Trash but not sending, so a person sends the replies the agent drafts. AgentMail can limit an API key's permissions. Its MCP OAuth sign-in uses your console identity, and the docs describe no way to narrow it.

AgentMail runs the service and stores messages in its own inboxes. Plans limit inboxes, monthly email volume, and storage. The free plan includes 3 inboxes, 3,000 emails a month, and 3 GB. Developer costs $20 a month for 10 inboxes, and Startup costs $200 a month for 150. The EU region, BYO cloud deployment, and dedicated IPs require Enterprise.

Mail stays with Gmail, Microsoft, or your IMAP provider. Fluxmail Cloud stores encrypted provider credentials but not messages, and self-hosted Fluxmail keeps its database and encrypted credentials on your host. Plans limit members and connected mailboxes, not monthly email volume. Self-hosted Personal is free for 3 mailboxes. In Cloud and self-hosted, Pro is $15 a month for 10 mailboxes and Business is $25 a month per member, with 20 mailboxes per member. Cloud also sets hourly limits on API calls and sends, and your email provider has its own sending limits.