Can my coding agent use Flowmails today?

Yes. Install the `flowmails-sdk` skill and the agent gets the SDK contract in every session; mint an API key in Settings → API Keys and it can send, wait for and read inbound mail, poll delivery status, and create a mailbox through `@flowmails/flowmails-sdk`. The hosted MCP server, the CLI and per-tool scoped credentials ship too.

Why not just give the agent an inbox password?

Because a password grants every folder and gives you no way to cut one off, and mail providers throttle or lock an account that sends like a machine. An API key scoped to one of your domains is revoked in one click, and every send lands in your own inbox where you can read exactly what went out.

Will an agent send mail to anyone without asking?

That is your agent's decision, not a Flowmails approval step. The blast radius is one mailbox: the key is bound to one of your domains, every send lands in your own outbox where you can read exactly what went out, and the key is revoked in one click. Email bodies are treated as untrusted input by the agent, never as instructions.

Self-hosted · CFFlowmails

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For AI coding agents

Self-hosted on Cloudflare

Email API for AI coding agents — an SDK, a skill, and a mailbox on your own domain

A coding agent does not need another inbox. It needs a mailbox it can call, on a domain it cannot spend by accident. Flowmails is a self-hosted email API on your Cloudflare account with four agent-facing entry points shipped today: the `@flowmails/flowmails-sdk` client, the `flowmails-sdk` skill that injects the send contract, the five error classes, and the retry policy into every session so the agent stops inventing method signatures, a hosted MCP server with scoped tools, and a `flowmails` CLI. The key is bound to one of your domains and revocable from the dashboard, so the blast radius is one mailbox rather than an SMTP credential. The listen half ships too: a durable wait for a verification mail answers immediately and resolves when the message lands, and the agent fetches the body only when it decides the message matters. A hosted MCP server with scoped tools and a `flowmails` CLI ship alongside them, so the same mailbox is reachable three ways.

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What hurts today

The ai coding agents pain points

Agents guess email APIs and invent method signatures, then retry against a surface that never existed

Handing an agent SMTP credentials means an unbounded blast radius when the prompt is wrong

Verification-mail flows degrade into polling loops that burn tokens and still miss the mail

How Flowmails answers

What you get instead

One command installs the skill: `npx skills add wms-why/flowmails-sdk-plugin@flowmails-sdk`

One typed call sends — `fm.send(SendOptions)` returns a typed `SendResult`, errors branch on `instanceof`

Keys are domain-bound and revocable; the from-address set can never drift off the zone

One durable wait resolves when the mail lands — `fm.waits.create` answers immediately, so no request is ever held open

FAQ

Common questions from ai coding agents

Other personas

All Flowmails for pages

For Indie developers For SaaS support teams For Agencies and studios For Privacy-sensitive products For Transactional email API