hydrology · Arcmap MCP: Risk & Policy

WHAT IT DOES

What hydrology does on Arcmap

AI agents invoke hydrology to trigger actions in Arcmap. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why hydrology needs a policy

The description is empty, so confidence is low. However, given the server context (ArcMap/arcpy control, sibling tools like execute_arcpy, contours, calculate_geometry), 'hydrology' most likely triggers geoprocessing/analysis operations such as flow direction, watersheds, or stream delineation via arcpy. These are Execute-category operations as they run spatial analysis workflows.

From the tool's definition Tool name 'hydrology' with empty description; server context indicates arcpy execution capabilities including 'execute_arcpy' sibling tool, suggesting this tool likely runs ArcPy hydrology analysis operations.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

hydrology Rate-limited

hydrology stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "hydrology": {
      "limits": [
        {
          "counter": "hydrology_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Arcmap, so you can run agents against it safely.

FAQ

Questions about hydrology

What does the hydrology tool do? +

hydrology. It is categorised as a Execute tool in the Arcmap MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on hydrology? +

Register the Arcmap MCP server in PolicyLayer and add a rule for hydrology: 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 Arcmap. Nothing to install.

What risk level is hydrology? +

hydrology is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit hydrology? +

Yes. Add a rate_limit block to the hydrology 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.

How do I block hydrology completely? +

Set action: deny in the PolicyLayer policy for hydrology. 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.

What MCP server provides hydrology? +

hydrology is provided by the Arcmap MCP server (pedralcg/arcmap-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.