Sofia Data MCP

TypeScript MCP server, stdio bridge, and CLI client for the Sofia municipality urban data portal at https://urbandata.sofia.bg.

Architecture

• Canonical server transport: Streamable HTTP
• Desktop compatibility transport: local stdio bridge that forwards to HTTP
• Local default endpoint: http://127.0.0.1:3000/mcp
• Source portal integration: CKAN Action API

Connect an MCP Client

The deployed server is public, requires no auth, and speaks Streamable HTTP at:

https://sofia-data-mcp-oparjiwnqa-ew.a.run.app/mcp

Clients with native remote/HTTP MCP support (recommended)

VS Code (Copilot Chat) — add to .vscode/mcp.json in your project (or your user mcp.json via the MCP: Open User Configuration command):

{
  "servers": {
    "sofia-data": {
      "type": "http",
      "url": "https://sofia-data-mcp-oparjiwnqa-ew.a.run.app/mcp"
    }
  }
}

Cursor — add to .cursor/mcp.json:

{
  "mcpServers": {
    "sofia-data": {
      "url": "https://sofia-data-mcp-oparjiwnqa-ew.a.run.app/mcp"
    }
  }
}

Clients that only support local stdio servers (e.g. Claude Desktop)

Claude Desktop's claude_desktop_config.json only launches local processes, so bridge to the remote HTTP endpoint with the widely-used mcp-remote adapter (no install/build required, runs via npx):

{
  "mcpServers": {
    "sofia-data": {
      "command": "npx",
      "args": [
        "-y",
        "mcp-remote",
        "https://sofia-data-mcp-oparjiwnqa-ew.a.run.app/mcp"
      ]
    }
  }
}

Alternatively, this repo's own @sofia-data/stdio-bridge package works the same way — point it at the deployed URL instead of running the server locally:

pnpm --filter @sofia-data/stdio-bridge dev -- \
  --upstream-url https://sofia-data-mcp-oparjiwnqa-ew.a.run.app/mcp

Quick smoke test (no client needed)

curl -s https://sofia-data-mcp-oparjiwnqa-ew.a.run.app/health

Packages

• @sofia-data/core: shared CKAN client, normalization, analytics, and MCP tool definitions
• @sofia-data/http-server: HTTP MCP server
• @sofia-data/stdio-bridge: stdio bridge to an HTTP MCP server
• @sofia-data/cli: bilingual CLI client

Requirements

• Node.js 24+
• Corepack available

Install

corepack enable
corepack prepare pnpm@10.8.1 --activate
pnpm install

Build

pnpm build

Run Locally

Start the HTTP server:

pnpm dev:server

Default endpoint:

http://127.0.0.1:3000/mcp

Run the CLI:

pnpm dev:cli

Run the stdio bridge:

pnpm dev:bridge

Override the bridge upstream URL:

pnpm --filter @sofia-data/stdio-bridge dev -- --upstream-url http://127.0.0.1:3000/mcp

Docker

Build and run with Docker Compose:

docker compose up --build

End-to-End Tests

packages/e2e runs a full black-box smoke test against a deployed instance (health check, MCP initialize handshake, listTools, and a real search_datasets call) — distinct from packages/http-server's unit tests, which spin up a local in-process server. It's skipped automatically (not failed) when no target is given, so it never affects normal pnpm test/CI:

E2E_BASE_URL=https://sofia-data-mcp-oparjiwnqa-ew.a.run.app pnpm test:e2e

This also runs automatically as a post-deploy gate in .github/workflows/deploy.yml, against the URL of the revision that was just deployed.

Deploying to Google Cloud Run

See deploy/gcp/README.md for scripts that deploy http-server to Cloud Run (capped at 1 instance) with an automated budget kill-switch that scales the service to zero if spend reaches a configured threshold (default $2).

Environment Variables

Copy .env.example and adjust as needed.

Key values:

• SOFIA_CKAN_BASE_URL
• HOST
• PORT
• MCP_HTTP_PATH
• REQUEST_TIMEOUT_MS=30000
• PREVIEW_MAX_BYTES=262144
• MAX_SEARCH_RESULTS=50
• CACHE_TTL_MS=300000 — in-memory TTL cache for CKAN reads (groups, organizations, search results, dataset lookups). Set to 0 to disable caching.
• ALLOWED_HOSTS / ALLOWED_ORIGINS — comma-separated extra hostnames/origins (beyond 127.0.0.1/localhost) allowed to reach the MCP endpoint. Required when deploying publicly (e.g. Cloud Run) so the server's own DNS-rebinding/CORS protection doesn't reject requests to its own public hostname. Left unset, the server only accepts local traffic.
• MCP_UPSTREAM_URL
• MCP_SERVER_URL

Tools

• search_datasets
• get_dataset
• list_groups
• get_group
• list_organizations
• get_organization
• list_dataset_resources
• preview_resource
• summarize_dataset
• find_related_datasets
• facet_datasets — returns catalog-wide counts (group/organization/format/license) computed by CKAN's native faceting, not a client-side count over a capped page of results

Dataset Metadata Enrichment

Dataset summaries include a semanticProfile field generated generically from CKAN metadata alone (groups, tags, resource formats) — there is no per-dataset hardcoded knowledge to maintain, so it scales automatically as datasets are added or renamed on the portal. For exact field-level structure, use summarize_dataset or preview_resource, which parse an actual sampled resource (JSON/GeoJSON) to report real geometry types and property/field names.

Group names that were corrupted by a source-side Cyrillic transliteration/encoding bug (e.g. bnopa3hoo6pa3ne) are automatically repaired using a generic transliteration of the group's title, rather than a hardcoded name-to-name mapping.

Testing

Each package has a unit test suite using Node's built-in test runner:

pnpm test

CI runs pnpm build, pnpm check (typecheck), and pnpm test on every push/PR to main (see .github/workflows/ci.yml).

Automated dependency updates

Dependabot (.github/dependabot.yml) checks weekly for updates to npm/pnpm packages, GitHub Actions, and the Docker base image, grouping patch/minor updates into a single PR per ecosystem. .github/workflows/dependabot-auto-merge.yml automatically approves and enables auto-merge for patch/minor version PRs; the merge only completes once the required build-and-test CI check passes on that PR (enforced by branch protection on main). Major version bumps are left for manual review.

Notes

• Technical naming is English-only.
• CLI display text is bilingual and rendered as two lines with English first.
• Source metadata from the portal is preserved as published.