Idescat MCP server

MCP (Model Context Protocol) server that exposes tools to query the official statistics of Catalonia, published by Idescat (Institut d'Estadística de Catalunya), from any MCP client (Claude, Windsurf, Cursor, VS Code, etc.).

• Public endpoint: https://api.idescat.cat/mcp
• Transport: Streamable HTTP (MCP spec 2025-06-18), stateless — each POST request is independent, with no sessions or SSE streams.
• Authentication: none required (the data is public).
• Data: official Idescat statistics in JSON-stat; labels and descriptions are in Catalan; territorial scope is Catalonia and its territorial breakdowns (counties, municipalities, provinces, etc.).

Installation

The public endpoint is https://api.idescat.cat/mcp. Add one of the snippets below to your MCP client's configuration. Different clients expect a different key (serverUrl, url, ...) and sometimes a type.

Windsurf/Devin, Antigravity (serverUrl)

{
	"mcpServers": {
		"idescat": {
			"serverUrl": "https://api.idescat.cat/mcp"
		}
	}
}

Cursor, Roo Code, Zoo Code (type: streamable-http)

{
	"mcpServers": {
		"idescat": {
			"type": "streamable-http",
			"url": "https://api.idescat.cat/mcp"
		}
	}
}

Cline (type: streamableHttp)

{
	"mcpServers": {
		"idescat": {
			"type": "streamableHttp",
			"url": "https://api.idescat.cat/mcp"
		}
	}
}

VS Code and the emerging standard form (servers, type: http)

{
	"servers": {
		"idescat": {
			"type": "http",
			"url": "https://api.idescat.cat/mcp"
		}
	}
}

Claude.ai (custom connector)

Claude.ai (web and desktop apps) can reach the remote server directly as a custom connector, no configuration file needed.

1. Open Customize → Connectors
2. Click Add custom connector.
3. Fill in the fields:
   • Name: Idescat
   • Remote MCP server URL: https://api.idescat.cat/mcp
4. Click Add. No authentication (OAuth / API key) is needed, since the data is public.
5. Back in a chat, enable the Idescat connector from the tools/attachments menu. Its tools and resources are now available to the assistant.
6. (Optional) In the connector's tool settings, switch each Idescat tool from Needs approval to Always allow so the assistant can run them without asking for confirmation every time. All the tools are read-only, so this is safe.

Claude Desktop and stdio-only clients (bridge with mcp-remote)

Clients that only speak stdio can reach the remote server through the mcp-remote bridge:

{
	"mcpServers": {
		"idescat": {
			"command": "npx",
			"args": ["-y", "mcp-remote", "https://api.idescat.cat/mcp"]
		}
	}
}

Not sure which key your client expects? (catch-all)

Most clients ignore keys they don't recognise, so this superset works with many of them at once:

{
	"mcpServers": {
		"idescat": {
			"url": "https://api.idescat.cat/mcp",
			"serverUrl": "https://api.idescat.cat/mcp",
			"type": "streamable-http",
			"streamableHttp": "https://api.idescat.cat/mcp"
		}
	}
}

Available tools

Available resources

Beyond the tools, the server exposes MCP resources — content a client can attach to the context without executing any action.

Static resources (resources/list):

Resource templates (resources/templates/list) — parametrised URIs:

The transport is stateless, so subscribe and resources/list_changed notifications are not offered (there is no persistent connection).

Agent skills

Two skills in the Agent Skills open format (a directory with a SKILL.md file: YAML frontmatter + Markdown instructions) teach agents how to use Idescat data correctly. They are published on the website and advertised in the ARD manifest:

Repository files

The following files define the server's guidance and resources and are served, unchanged, to MCP clients:

• instructions.md — usage guidance the server sends to clients during the handshake and exposes as the idescat://instructions resource. It explains how to choose a statistic, the data-retrieval flow, how to interpret JSON-stat, and the source-attribution rules.
• resources.json — declaration of the MCP resources and resource templates the server exposes (the two tables in the Available resources section above), including each URI, title, description, MIME type, and its backing file or tool.
• resources/geo.md — glossary of territorial codes (cat, prov, at, com, mun, dis, sec) used by the geo parameter, exposed as the idescat://glossary/geo resource.

The repository also includes:

• server.json — the server's metadata manifest in the standard server.json format, used to publish the server to the official MCP Registry.
• jsonstat/SKILL.md and workflow/SKILL.md — the two agent skills, also published on the website under https://www.idescat.cat/dev/api/taules/.

Discovery (Agentic Resource Discovery)

The server is advertised using the Agentic Resource Discovery (ARD) specification (v0.91) so agents can find it automatically:

• An ARD manifest is published at https://www.idescat.cat/.well-known/ard.json and https://api.idescat.cat/.well-known/ard.json. The legacy predecessor path (/.well-known/ai-catalog.json) is redirected (301) to the new manifest. The manifest advertises four entries: this MCP server (application/mcp-server-card+json), the Idescat Tables API, described by its OpenAPI document (application/openapi+json) at https://www.idescat.cat/dev/api/taules/openapi.json, and the two agent skills (text/markdown; profile="urn:air:agent-skills").
• A GET request to the endpoint https://api.idescat.cat/mcp returns the MCP server card (application/mcp-server-card+json), generated from the server's tool and resource definitions. A GET requesting text/event-stream returns 405, since this stateless server offers no SSE stream.
• The MCP server card is also served at https://www.idescat.cat/.well-known/mcp/server-card.json (and https://www.idescat.cat/.well-known/mcp.json), which redirects to https://api.idescat.cat/mcp.
• The website pages also include a link to the manifest: <link rel="ard" href="/.well-known/ard.json" type="application/json"> (the ard link relation replaces the predecessor ai-catalog relation).
• robots.txt includes an Agentmap: directive pointing to the manifest.
• The MCP server is also advertised in the site's llms.txt file.

MCP Registry

The server is listed in the official MCP Registry under the name cat.idescat/mcp (see server.json). MCP clients and aggregators can retrieve its metadata from the registry API:

https://registry.modelcontextprotocol.io/v0.1/servers/cat.idescat%2Fmcp

Interactive testing with MCP Inspector

npx @modelcontextprotocol/inspector@2.0.0

Pinning a specific version (e.g. @2.0.0) keeps the tool reproducible and avoids picking up unexpected changes; it requires Node.js >= 22.19.0. Any npm warn deprecated ... / ERESOLVE messages come from the Inspector's own dependencies and are harmless — they do not affect this MCP server.

Select the "Streamable HTTP" transport and enter the endpoint URL.

Links