指定した矩形範囲内の水域・河川データをGeoJSON形式で取得します。川、湖、海、運河などの水域情報が含まれます。
AI agents call get_waterways to retrieve information from OSM-GeoJSON-MCP-Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This is a data retrieval operation with no side effects. It queries an external data source (OpenStreetMap) and returns geographic information in a standard format for analysis and visualization. There is no capability to modify, delete, or execute code. The blast radius of misuse is minimal—an agent could retrieve unwanted geospatial data but cannot cause harm beyond information disclosure.
From the tool's definition Tool description states it 'retrieves' (取得します) waterway and water body data in GeoJSON format from a specified rectangular area.
Documented attack patterns abuse exactly the kind of access get_waterways gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and OSM-GeoJSON-MCP-Server, and nothing reaches the server without passing your rules. This is the rule we recommend for get_waterways:
{
"version": "1",
"default": "deny",
"tools": {
"get_waterways": {}
}
}get_waterways is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
Free to start. No card required.
指定した矩形範囲内の水域・河川データをGeoJSON形式で取得します。川、湖、海、運河などの水域情報が含まれます。. It is categorised as a Read tool in the OSM-GeoJSON-MCP-Server MCP Server, which means it retrieves data without modifying state.
Register the OSM-GeoJSON-MCP-Server MCP server in PolicyLayer and add a rule for get_waterways: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches OSM-GeoJSON-MCP-Server. Nothing to install.
get_waterways is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the get_waterways rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for get_waterways. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
get_waterways is provided by the OSM-GeoJSON-MCP-Server MCP server (shimizu/osm-geojson-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from OSM-GeoJSON-MCP-Server, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
11 OSM-GeoJSON-MCP-Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.