@rampstack/umami-mcp

A read-only Model Context Protocol server for Umami Cloud analytics. It exposes your Umami website data to MCP clients (Claude Code, Claude Desktop, and others) as a small set of GET-only tools.

Read-only by construction: the server makes exactly one kind of network call, an authenticated HTTP GET against the Umami Cloud API. There is no write path in the code, so no tool can create, edit, or delete anything in your Umami account.

Install

One line for Claude Code (user scope):

claude mcp add umami --scope user \
  --env UMAMI_API_KEY=your_key_here \
  -- npx -y @rampstack/umami-mcp

Claude Desktop (claude_desktop_config.json):

{
  "mcpServers": {
    "umami": {
      "command": "npx",
      "args": ["-y", "@rampstack/umami-mcp"],
      "env": {
        "UMAMI_API_KEY": "your_key_here"
      }
    }
  }
}

Environment

Variable	Required	Default	Notes
UMAMI_API_KEY	yes	none	Umami Cloud API key. The server exits if missing.
UMAMI_API_BASE	no	https://api.umami.is/v1	Override for a regional base, e.g. .../v1/eu.

Get a key from the Umami Cloud dashboard under Settings -> API keys. The key is passed to Umami in the x-umami-api-key header (docs).

Tools

All tools take dates as ISO 8601 or epoch milliseconds. Naive datetimes (no timezone) are treated as UTC. Every time-scoped response echoes the resolved { startAt, endAt } epoch window so you can verify the exact window queried.

Tool	Purpose
list_websites	id, name, domain for every site on the account. Call first to get website_id.
get_stats	visitors, visits, pageviews, bounces, totaltime + previous period + computed deltas.
get_pageviews	pageviews/sessions timeseries, bucketed by day or hour.
get_metrics	top values for one dimension (url, referrer, browser, os, device, country, event).
get_event_data	custom event-data properties (plan-gated; see below).
cohort_report	one call: stats + top 10 urls + top 10 referrers + top 10 events over a range.

cohort_report accepts a range of 24h, 7d, 30d, 90d, or an ISO start/end pair like 2026-01-01/2026-02-01.

Note on metric types

Umami's current docs label the URL dimension path. This server exposes it as url, the long-standing alias the API still accepts, matching the Umami web UI vocabulary. Other dimensions (referrer, browser, os, device, country, event) map directly.

Note on event-data

The get_event_data tool calls the Umami event-data endpoints, which are gated by account plan. On tiers where they are not exposed, the tool returns a clear note (not fabricated data) and points you to get_metrics with type=event for event counts, which is available everywhere.

Troubleshooting

Every call fails with "Network error reaching Umami" / fetch failed. The server never reached the Umami API — this is a transport error, not an API response. Check the unwrapped cause code in the message:

• UNABLE_TO_VERIFY_LEAF_SIGNATURE (or another certificate error) means a TLS interceptor — antivirus (e.g. AVG, Kaspersky) or a corporate proxy (Zscaler, Netskope) — is re-signing HTTPS with a root CA that lives in the OS trust store. Node ships its own CA bundle and ignores the OS store by default, so it rejects the chain. Fix it by telling Node to trust the OS store:

  claude mcp add umami --scope user -- node --use-system-ca /path/to/dist/index.js

  --use-system-ca (Node 20.6+/22+) trusts the Windows/macOS certificate store where the interceptor's root CA is installed. Prefer this over exporting the CA by hand, and never disable verification with NODE_TLS_REJECT_UNAUTHORIZED=0 — that would send your API key over an unverified connection.

• ENOTFOUND / ECONNREFUSED / ETIMEDOUT point at DNS or connectivity to the configured UMAMI_API_BASE, not a certificate problem.

Security

• Read-only by construction. The client exposes a single get() method; there is no POST/PUT/DELETE anywhere in the source.
• GET-only. Every tool maps to a documented Umami GET endpoint.
• Key stays local. UMAMI_API_KEY is read from your environment and sent only in the x-umami-api-key request header. It is never logged, never written to disk, and never included in error messages.
• No telemetry. The server makes no calls other than to the Umami API base you configure.
• MIT licensed.

The Umami Cloud API key has account-wide read scope. If you manage analytics for multiple clients, use a separate Umami team or account per client rather than one key that can read them all.

Development

Requires Node 20+.

npm install
npm run build   # tsc -> dist/
npm test        # compiles and runs the node:test suite (mocked fetch, no live API)

Tests never make live API calls and never reference a real key.

Publishing

This package is not yet published. To publish (maintainer action):

npm run build
npm publish --access public

License

MIT. See LICENSE.