Manage subscribers and send campaigns on a self-hosted Sendy newsletter installation.
Sendy ships in the w6w first-party pack. It declares 8 actions, 2 health checks, and the host runs its code in a sandbox that never sees the credential.
io.w6w.sendySendy is self-hosted newsletter software that sends through your own Amazon SES account. It has no vendor host of its own — every workflow talks to the operator’s own installation — so this app covers Sendy’s documented HTTP API exactly as published at sendy.co/api: adding, removing and deleting subscribers, reading a subscriber’s status and a list’s active count, listing lists and brands, and creating (optionally sending or scheduling) a campaign.
Because Sendy ships as software you run yourself, there is no vendor status to watch — the API’s own error text is the only signal a workflow gets, and this app reads it literally rather than guessing from an HTTP status code.
Three routes to the same 8 actions. The Workflow tab is generated from Sendy's own manifest and carries its real ids, so it is copy-pasteable; the Code and CLI examples are the same call for any action on any app, so every app-specific value in them is a blank you fill in.
campaign-create Create a draft campaign, or create and send/schedule one. Requires a cron job configured on the Sendy installation for sending to actually happen.
subscriber-status Current status of a subscriber in a list (subscribed, unsubscribed, bounced, …).
A workflow step names the app and the action, and the editor fills in the
connection when you pick one. This is the Step shape from the
workflow spec, carrying Sendy's real ids.
{
"manifestVersion": "2",
"name": "sendy-example",
"steps": [
{
"id": "campaign-create",
"uses": {
"app": "io.w6w.sendy",
"action": "campaign-create",
"connection": "conn_YOUR_CONNECTION_ID"
},
"with": {
"fromName": "<fromName>",
"fromEmail": "<fromEmail>",
"replyTo": "<replyTo>"
}
}
]
}campaign-create brand-list list-list subscriber-active-count subscriber-status +3 more actions available
Every app-specific value here is a blank you have to fill in. An
app action is reached through the connection that authenticates it, so the
address is a connection id, not the app id — and connections belong to your account,
so a public page cannot know yours. Create one for Sendy, then fill in
the three blanks: conn_YOUR_CONNECTION_ID, the action key, and the
parameters that action declares. The call itself is real — the shape is transcribed
from the studio's own snippet builder, which prints the same kind of blanks — but
nothing in it is specific to Sendy. The Workflow tab is where this app's
real ids are.
npm install @w6w/sdkyarn add @w6w/sdkpnpm add @w6w/sdkdeno add npm:@w6w/sdkimport { W6wClient, isActionRun } from "@w6w/sdk";
// Reads W6W_BASE_URL and W6W_TOKEN from the environment when omitted.
const client = new W6wClient();
const envelope = await client.run({
urn: "conn_YOUR_CONNECTION_ID",
action: "campaign-create",
payload: {
fromName: "<value>",
fromEmail: "<value>",
replyTo: "<value>",
title: "<value>",
subject: "<value>",
htmlText: "<value>",
// plainText: "<value>",
// listIds: "<value>",
// segmentIds: "<value>",
// excludeListIds: "<value>",
// excludeSegmentIds: "<value>",
// brandId: "<value>",
// queryString: "<value>",
// trackOpens: "<value>",
// trackClicks: "<value>",
// sendCampaign: "<value>",
// scheduleDateTime: "<value>",
// scheduleTimezone: "<value>",
},
});
if (isActionRun(envelope)) console.log(envelope.value); npm install -g @w6w/cli w6w run conn_YOUR_CONNECTION_ID --action campaign-create --payload '{"fromName":"<value>","fromEmail":"<value>","replyTo":"<value>","title":"<value>","subject":"<value>","htmlText":"<value>"}' Give an AI agent Sendy — without giving it Sendy's credentials. One MCP endpoint exposes every app, function and workflow the caller is entitled to, as tools it can discover and run. Access is granted per team while we onboard.
One tool call{
"name": "w6w_invoke",
"arguments": {
"ref": "app:io.w6w.sendy#campaign-create",
"input": {
"fromName": "<fromName>",
"fromEmail": "<fromEmail>",
"replyTo": "<replyTo>"
}
}
}
Every tool names its target with a single ref. The
app: form above doesn't name a connection at all — the
host resolves which of the caller's Sendy connections to sign
with, and refuses rather than guesses when the answer is ambiguous.
The token is attached host-side, at the moment of the call. It is never a tool argument, never in the model's context, and never in a transcript — so a prompt injection has nothing to exfiltrate.
Tools are derived per end user from what that person has actually connected and is entitled to — not one shared bot identity carrying the union of everyone's access.
Multi-step work runs on the workflow engine and returns a run handle the agent can poll — retries, branching and state survive the conversation that started them.
Sendy's declared health checks are on the surface too, so an agent can tell "the vendor is down" from "your credential expired" before it burns a retry on either.
The MCP surface is part of the hosted platform. Sendy itself is MIT, and the runtime that executes it is source-available (FSL).
Sendy declares its own checks, so its health is a property of the app rather than something the host guesses at.
Unauthenticated POST to /api/brands/get-brands.php against this connection's own installation. Sends no api_key — an expired or wrong key must not make a live installation look down.