Signal by StackEnhance

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	800+ 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 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 and add it.

Or add it by hand:

1. Open Settings → Apps & Connectors → Advanced and turn on Developer mode.
2. Choose Create.
3. Name: Signal by StackEnhance. URL: https://mcp.stackenhance.com/mcp. Authentication: None.
4. 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: [email protected]
• 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.

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Built by Stack Enhance AB, Sweden.