ontario-data-mcp

[!IMPORTANT]
Beta: This project is under active development. The data structure and tool interfaces may change. LLM-generated analysis may contain errors. Always verify critical findings against the returned source data.

This is an MCP server for discovering, downloading, querying, and analyzing datasets from Ontario's Open Data portals. It allows asking questions of the data in English (or Spanish, Chinese, French, etc).

It currently supports the Ontario, Toronto, Ottawa, Waterloo, Kitchener, and Region of Waterloo portals, and utilizes a shared DuckDB cache for fast SQL queries, statistical analysis, and geospatial operations.

Contributing

Contributions welcome! To get started, see Installation below.

Found a bug? Have an idea? Discovered something interesting? Open an issue here: https://github.com/sprine/ontario-data-mcp/issues

Features

• find - search across supported Ontario open data portals
• download - retrieve and cache datasets
• query - run SQL, statistical, and geospatial analysis via DuckDB
• validate — verify that data claims are supported by query results
• A shared DuckDB cache for high-performance analytics

Architecture

flowchart TD
    Client["AI Client<br/>(Claude Code · VS Code · etc.)"]

    subgraph Server["ontario-data-mcp (FastMCP)"]
        direction TB

        subgraph Tools["MCP Tools"]
            direction LR
            T1["Discovery"]
            T2["Metadata"]
            T3["Retrieval"]
            T4["Querying"]
            T5["Geospatial"]
            T6["Quality & Validation"]
        end

        PC["Portal Clients<br/>CKANClient · ArcGISHubClient"]
        Cache[("DuckDB Cache<br/>~/.cache/ontario-data/")]

        Tools -->|"fan out to all portals"| PC
        T3 & T5 -->|"download → store"| Cache
        T4 & T6 -->|"SQL queries"| Cache
    end

    subgraph Portals["Open Data Portals"]
        direction LR
        CKAN["Ontario · Toronto<br/>CKAN API"]
        ArcGIS["Ottawa · Waterloo · Kitchener<br/>Region of Waterloo<br/>ArcGIS Hub"]
    end

    Client <-->|"MCP Protocol"| Tools
    PC -->|"CKAN 2.8"| CKAN
    PC -->|"OGC Records / Hub v3"| ArcGIS

Data flow: Discovery and metadata tools fan out to all portals in parallel. Retrieval tools download data and store it in a local DuckDB cache. Querying and quality tools run fast SQL locally against the cache — no repeated API calls.

Installation

With Claude Code

claude mcp add ontario-data -- uvx ontario-data-mcp

To auto-approve all tool calls (no confirmation prompts), add to your Claude Code settings:

{
  "permissions": {
    "allow": ["mcp:ontario-data:*"]
  }
}

Tools are annotated as read-only or destructive per the MCP spec. Download tools populate the local cache but are read-only (no remote mutations). Destructive tools (cache_manage, refresh_cache) only modify local cached data.

Add to .vscode/mcp.json:

{
  "mcpServers": {
    "ontario-data": {
      "command": "uvx",
      "args": ["ontario-data-mcp"]
    }
  }
}

git clone https://github.com/sprine/ontario-data-mcp
cd ontario-data-mcp
uv sync
uv run ontario-data-mcp

To connect from source to Claude Code:

Note: MCP subprocesses don't inherit your shell's PATH, so you must use the absolute path to uv (find it with which uv).

claude mcp add ontario-data -- /absolute/path/to/uv run --directory /path/to/ontario-data-mcp ontario-data-mcp

Supported Portals

All searches fan out to every portal by default — no need to select a portal. Dataset and resource IDs are prefixed with their portal (e.g. toronto:abc123).

List of tools available to the AI agent

MCP Resources

Resources the agent can read for context without calling a tool:

Prompts

Context-aware guided workflow prompts:

• explore_topic — Guided exploration of a topic (fetches live catalogue context)
• data_investigation — Deep dive into a specific dataset: schema, quality, statistics
• compare_data — Side-by-side analysis of multiple datasets

Environment Variables

Development

uv sync
uv run python -m pytest tests/ -v

License

MIT — see LICENSE for the software.

Data accessed through this tool is provided under the following open government licences:

• Contains information licensed under the Open Government Licence – Ontario.
• Contains information licensed under the Open Government Licence – Toronto.
• Contains information licensed under the Open Government Licence – City of Ottawa.
• Contains information licensed under the City of Waterloo Open Data Licence.
• Contains information licensed under the Open Government Licence - The Corporation of the City of Kitchener.
• Contains information licensed under the Region of Waterloo Open Data Licence v.2.0.