mcp-arcgis — ArcGIS Online (AGOL) MCP server

A FastMCP server for searching content and querying hosted feature layers in ArcGIS Online. It talks to the AGOL Sharing REST and Feature Service REST APIs directly with requests — no heavy arcgis Python package required.

Read-only by design. It searches items and queries features; it never adds, updates, or deletes anything.

Tools

Connection / discovery

• whoami — signed-in user + portal info (connectivity smoke test)

• search_items — search org/public content (query, item_type, sort_field)

• get_item — full portal metadata for an item id

• get_item_data — an item's /data payload (a Web Map's operational layers, an app/dashboard config); trace which feature services a map uses

• list_layers — layers & tables of a feature service (ids, names, geometry types)

• describe_layer — fields, geometry type, extent, record count for one layer

Query

• query_features — attribute/paged query → {count, exceededTransferLimit, features}

• count_features — count matching a where clause (cheap sizing before a pull)

• aggregate_features — server-side group-by statistics (SUM/AVG/COUNT/MIN/MAX/STDDEV/VAR) via outStatistics; no rows pulled

• distinct_values — distinct value combinations of one or more fields (discover categories/codes)

• spatial_query — query features by geometry (point/envelope/polygon), optionally buffered by a distance

Identify a layer to describe/query by either a feature-service item_id (+ layer_index, default 0) or a direct service_url (a .../FeatureServer root plus layer_index, or a full .../FeatureServer/0 layer URL).

Example

search_items(query="parcels", item_type="Feature Service")
list_layers(item_id="abcd1234…")
describe_layer(item_id="abcd1234…", layer_index=0)
count_features(item_id="abcd1234…", where="STATUS = 'Active'")
query_features(item_id="abcd1234…", where="ACRES > 5",
               out_fields="OBJECTID,NAME,ACRES", order_by="ACRES DESC", limit=50)

# distinct values in a field, then a grouped rollup
distinct_values(item_id="abcd1234…", fields="STATUS")
aggregate_features(item_id="abcd1234…", group_by="STATUS", order_by="sum_ACRES DESC",
                   statistics=[{"statisticType":"count","onStatisticField":"OBJECTID",
                                "outStatisticFieldName":"n"},
                               {"statisticType":"sum","onStatisticField":"ACRES"}])

# everything within 500 m of a lat/long point
spatial_query(item_id="abcd1234…", geometry={"x":-79.38,"y":43.65},
              geometry_type="esriGeometryPoint", distance=500, units="esriSRUnit_Meter")

# which feature services does a web map reference?
get_item_data(item_id="webmap-item-id…")

Related MCP server: ArcGIS MCP

Auth

Set "auth" in config.json:

url is your organization's portal (e.g. https://yourorg.maps.arcgis.com) or https://www.arcgis.com. max_records caps how many features a single query_features call returns (default 2000); page with offset for more.

No secrets live in config.json — only the name of an environment variable.

Setup

python -m venv .venv
.\.venv\Scripts\python.exe -m pip install -r requirements.txt
copy config.example.json config.json     # edit url + username
copy .env.example .env                    # set ARCGIS_PASSWORD
.\.venv\Scripts\python.exe server.py      # smoke test (Ctrl+C to stop)

Register with an MCP client

See examples/mcp.json — point command at the venv's python.exe and args at server.py, using absolute paths.

Use with Claude Desktop

Claude Desktop reads MCP servers from claude_desktop_config.json (Settings → Developer → Edit Config). Add this server under mcpServers with absolute paths to the venv Python and server.py, then fully quit and reopen Claude Desktop.

License

MIT — see LICENSE.