Open-source B2B and marketplace ecommerce; new stores include an MCP server for AI agents.
Signal by StackEnhance
Overview
Description from the maker (original English)
How often 750+ e-commerce brands send marketing emails: counts, send dates, recent subject lines.
PopNx MCP’s three pillars
These three are never merged into one score: opinions, measurements and popularity are different things.
- User voiceiNo reviews yetReviews open together with accounts in a later step
- Our basic checksi1 of 1 passedChecked from public information; code not scanned yet
- UsageiNot measured yet★ –
What you can do with it
We have not written a plain-language summary for this one yet. Below are the facts we read from the registry.
- Connection: Runs in the cloud
- Transport: Streamable HTTP
- Category: Online shops & payments
Install
Pick the AI app you use, then copy the settings.
Before you install
- Basic checks: 1 of 1 passed
- Runs on the maker’s server: what you ask it goes through their server.
- The registry lists no key to fill in.
You need
- Runs in the cloudNothing to install; it connects over the internet
Which app do you use?
Pick your app above. We remember it, so next time the button says “Install in …”.
Works in Claude on the web, desktop and mobile:
- Open Settings → Connectors
- Press Add custom connector
- Paste the address below and press Add
- If it asks you to sign in, sign in with the maker
https://mcp.stackenhance.com/mcpRun this in your terminal
claude mcp add --transport http signal https://mcp.stackenhance.com/mcpOr copy the settings yourself
Paste into .cursor/mcp.json in your project, or ~/.cursor/mcp.json
{
"mcpServers": {
"signal": {
"url": "https://mcp.stackenhance.com/mcp"
}
}
}Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.
Or copy the settings yourself
Paste into .vscode/mcp.json in your project
{
"servers": {
"signal": {
"type": "http",
"url": "https://mcp.stackenhance.com/mcp"
}
}
}Your browser asks to open the app, then the app shows the settings and asks you to confirm. Key values are left empty for you to fill in.
ChatGPT connects only to servers on the internet:
- Open ChatGPT on the web → Settings → Connectors (Apps)
- Press Create or Add (some plans need Developer mode under Advanced first)
- Paste the address below, give it a name and save
- If it asks you to sign in, sign in with the maker
https://mcp.stackenhance.com/mcpMenu names can differ slightly by plan and over time.
Your choice stays on this device in a cookie; no account needed.
These settings are generated from the maker’s registry entry. If the README says otherwise, follow the README.
What it can do
We have not read this server’s tool list yet; we check endpoints in rotation.
Basic checksi
We check information anyone can see; we have not read the code. Checks that do not apply are left out of the count. · Checked Nov 6, 2026
- ✓ Pass
Maker matches the repo
The registry name was verified against the domain stackenhance.com (the registry checks domain ownership)
- … Not checked yet
Still maintained
We have not read this repo from GitHub yet
- … Not checked yet
Has a licence
We have not read this repo from GitHub yet
- … Not checked yet
Endpoint responds
Not checked yet; we check endpoints in rotation
- … Not checked yet
Sign-in with OAuth
Not checked yet; we check endpoints in rotation
- … Not checked yet
No hidden instructions in tool descriptions
Not checked yet; we read the tool list when we check the endpoint
Compared with others in Online shops & paymentsi
- More stars than 0% of the other 1743 servers in this category
- Published to the registry more recently than 55% of the other 1743 servers in this category
- Basic checks equal to or better than 100% of the other 1743 servers in this category
Compared with every active server in this category in the registry. Stars count only when the publisher owns the repo.
Common questions
Is Signal by StackEnhance safe?
It passed 1 of 1 applicable basic checks. We have not read the code. Before adding a key or token, see what access the server asks for and use a key with only the permissions you need.
What keys or codes does it need?
The registry does not list a required key, though some servers ask you to sign in on first use.
Does it run on my computer or in the cloud?
It runs in the maker’s cloud. Connect over the internet with nothing to install, but what you send passes through the maker’s servers.
Is it still maintained?
The GitHub repo last changed –, and the latest version (1.2.0) reached the registry 26 days ago.
Which apps can use it?
Apps that support MCP, such as Claude Desktop, Claude Code, Cursor and VS Code. It connects by URL, so apps that accept remote MCP servers work too, such as ChatGPT in developer mode.
What can I use instead?
In the same category: Spree Commerce: open-source B2B and marketplace ecommerce, Stripe MCP, MCP Cn Commerce
Alternatives
Servers in the same category from other makers, sorted by stars.
Reading a card:★ GitHub starsiThree pillars: reviews · checks · usageiUpdated = latest version published to the registryi
Stripe MCP
Stripe’s official server lets AI view and manage customers, products, payments and invoices. Connect to Stripe’s cloud and sign in with OAuth.
MCP Cn Commerce
8 read-only MCP platform entries; support is operation-specific; merchant live acceptance pending
README from the maker
Open the README
Copied from the maker’s repo as written. PopNx MCP has not reviewed or endorsed it. HTML, images and scripts are removed. Links lead off this site.
Signal by StackEnhance — MCP server
Marketing-email intelligence for e-commerce brands in the Nordics and Germany, inside your AI assistant.
Signal by StackEnhance is a free, read-only Model Context Protocol server. It lets Claude, ChatGPT, Cursor and other MCP clients answer questions about how often online stores send marketing email, and when, from the archive behind StackEnhance Signal.
https://mcp.stackenhance.com/mcp
Streamable HTTP · no API key · no sign-in · read-only · free
What you can ask
- *How often does Boozt email its customers in Sweden?*
- *What did Lindex send last week?*
- *How many emails did IKEA send in August?*
- *Which home and interior brands in Denmark email most often?*
- *Is Gina Tricot still sending newsletters?*
Every answer links to the brand's public page on stackenhance.com as its source.
The data
| Brands | 10,000+ online stores, mostly in Sweden, Norway, Denmark, Finland and Germany |
| Emails | 80,000+ marketing emails captured |
| What counts | De-duplicated campaign sends. Welcome, birthday and transactional emails are excluded. |
| Frequency | Average marketing emails per week over the last 90 days |
| Dates | The brand's local calendar date |
| Not available | Open, click or revenue data (Signal has none), full campaigns, offers, products and creative analysis |
For a period of up to 31 days the server lists the date of each send. It may quote up to two subject lines, and only ones already shown on the brand's public page.
Tools
| Tool | Answers | Inputs |
|---|---|---|
get_brand_summary | A brand's profile: market, category, first observed, total emails, current emails per week, latest campaign date | brand, optional market |
get_brand_email_frequency | How many marketing emails a brand sent in a period, and on which days (periods up to 31 days) | brand, from, to (YYYY-MM-DD, up to two years), optional market |
find_brands | Brands in one market ranked by current email frequency, optionally within a category | market (SE, NO, DK, FI, DE), optional category, limit (1–10) |
All three are read-only and idempotent. A brand can be given by name (Lindex) or domain (lindex.com). Without a market, a brand sold in several countries returns one result per market.
Setup
Claude (web, desktop and mobile)
Open [Signal by StackEnhance in Claude's directory](https://claude.ai/directory/signal-by-stackenhance) and click Connect.
Or add it by hand: Settings → Connectors → Add custom connector, name it Signal by StackEnhance, paste the server URL and leave the OAuth fields empty.
ChatGPT
Open [Signal by StackEnhance in ChatGPT's app directory](https://chatgpt.com/plugins/plugin_asdk_app_6ac8b32270388191b0dfcfae9d88c30a) and add it.
Or add it by hand:
- Open Settings → Apps & Connectors → Advanced and turn on Developer mode.
- Choose Create.
- Name:
Signal by StackEnhance. URL:https://mcp.stackenhance.com/mcp. Authentication: None. - Start a new chat and turn the connector on from the + menu.
Claude Code
claude mcp add --transport http signal-by-stackenhance https://mcp.stackenhance.com/mcp
Cursor
~/.cursor/mcp.json, or .cursor/mcp.json in a project:
{
"mcpServers": { "signal-by-stackenhance": { "url": "https://mcp.stackenhance.com/mcp" } } }
VS Code
.vscode/mcp.json:
{
"servers": { "signal-by-stackenhance": { "type": "http", "url": "https://mcp.stackenhance.com/mcp" } } }
Windsurf
~/.codeium/windsurf/mcp_config.json:
{
"mcpServers": { "signal-by-stackenhance": { "serverUrl": "https://mcp.stackenhance.com/mcp" } } }
Clients that only run local (stdio) servers
Bridge to the remote server with mcp-remote:
{
"mcpServers": { "signal-by-stackenhance": { "command": "npx", "args": ["-y", "mcp-remote", "https://mcp.stackenhance.com/mcp"] } } }
Privacy
When an assistant uses the server, StackEnhance receives only the tool request (the brand, market, category, date range or number of results asked about) and technical request data, such as the IP address of the system that connects. When ChatGPT or Claude call the server from their own infrastructure, that is normally the AI provider's address, not yours. The server never receives your conversation or your identity, and nothing it receives is linked to an account. Full details: privacy policy, section 13.
Limits
Use is free and subject to a fair-use rate limit per IP address. Answers are aggregates of what Signal observed; a brand Signal does not track, or tracks with too little data, is reported as not available rather than guessed.
Support
- Help: Ask Signal questions in ChatGPT and Claude
- Email: support@stackenhance.com
- Privacy policy · Terms of service
Development
npm install
npm run dev # http://localhost:3333/mcp, against the production facts API npm test
SIGNAL_API_URL points the server at another facts API; SIGNAL_MCP_KEY is an optional key that gives a deployment its own rate-limit tier. The server has no database access: its only data source is the public Signal facts API.
Built by Stack Enhance AB, Sweden.