<!-- mcp-name: ontario-data-mcp -->

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.

<details> <summary>With VS Code</summary>

Add to .vscode/mcp.json:

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

</details>

<details> <summary>From Source</summary>

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

</details>

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).

Portal	Platform	Datasets
ontario	CKAN	~5,700
toronto	CKAN	~533
ottawa	ArcGIS Hub	~665
waterloo	ArcGIS Hub	~129
kitchener	ArcGIS Hub	~219
region-waterloo	ArcGIS Hub	~125

List of tools available to the AI agent

<details> <summary><b>Discovery</b> (5 tools)</summary>

Tool	Description
search_datasets	Search for datasets across all portals (or narrow with portal=)
list_portals	List all available portals with platform type
list_organizations	List government ministries with dataset counts
list_topics	List all tags/topics in the catalogue
find_related_datasets	Find datasets related by tags and organization

</details>

<details> <summary><b>Metadata</b> (4 tools)</summary>

Tool	Description
get_dataset_info	Get full metadata for a dataset (use prefixed ID like toronto:abc123)
list_resources	List all files in a dataset with formats and sizes
get_resource_schema	Get column schema and sample values for a datastore resource
compare_datasets	Compare metadata side-by-side for multiple datasets (cross-portal)

</details>

<details> <summary><b>Retrieval & Caching</b> (4 tools)</summary>

Tool	Description
download_resource	Download a resource and cache it in DuckDB (use prefixed ID like toronto:abc123)
cache_info	Cache statistics + list all cached datasets with staleness
cache_manage	Remove a single cached resource or clear the entire cache
refresh_cache	Re-download cached resources with latest data

</details>

<details> <summary><b>Querying</b> (4 tools)</summary>

Tool	Description
query_resource	Query a resource via CKAN Datastore API (remote)
sql_query	Run SQL against the CKAN Datastore (remote)
query_cached	Run SQL against locally cached data in DuckDB
preview_data	Quick preview of first N rows of a resource

</details>

<details> <summary><b>Data Quality</b> (3 tools)</summary>

Tool	Description
check_freshness	Check if a dataset is current vs. its update schedule
profile_data	Statistical profile using DuckDB SUMMARIZE
validate_result	Validate that a data claim is supported by query results

</details>

<details> <summary><b>Geospatial</b> (3 tools)</summary>

Tool	Description
load_geodata	Cache a geospatial resource (SHP, KML, GeoJSON) into DuckDB
spatial_query	Run spatial queries against cached geospatial data
list_geo_datasets	Find datasets containing geospatial resources

</details>

MCP Resources

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

URI	Description
ontario://cache/index	List of all locally cached datasets with freshness info
ontario://dataset/{dataset_id}	Full metadata for a specific dataset (supports prefixed IDs)
ontario://portal/stats	Overview statistics across all data portals
ontario://schema/{table_name}	Column schema, types, sample values, and type warnings for a cached table
ontario://guides/duckdb-sql	DuckDB SQL reference for Ontario open data analysis

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

Variable	Default	Purpose
ONTARIO_DATA_CACHE_DIR	~/.cache/ontario-data	DuckDB storage + log file location
ONTARIO_DATA_TIMEOUT	30	HTTP timeout in seconds
ONTARIO_DATA_RATE_LIMIT	10	Max CKAN requests per second

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.