fcm_discovery · DoWhy MCP v2 0 MCP: Risk & Policy

WHAT IT DOES

What fcm_discovery does on DoWhy MCP v2 0

AI agents invoke fcm_discovery to trigger actions in DoWhy MCP v2 0. 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 fcm_discovery needs a policy

Causal model discovery involves executing a computational process (fitting/inference algorithms) against data to learn causal structure. It is not a simple read/query, nor does it delete or move money. It falls under Execute because it triggers an external analytical operation whose effects (the discovered model) depend on the input arguments and data.

From the tool's definition '发现函数因果模型' translates to 'discover functional causal model using DoWhy' — implies running a causal discovery algorithm (model fitting/execution) over data

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

fcm_discovery Rate-limited

fcm_discovery 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": {
    "fcm_discovery": {
      "limits": [
        {
          "counter": "fcm_discovery_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 DoWhy MCP v2 0, so you can run agents against it safely.

FAQ

Questions about fcm_discovery

What does the fcm_discovery tool do? +

使用 DoWhy 发现函数因果模型. It is categorised as a Execute tool in the DoWhy MCP v2 0 MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on fcm_discovery? +

Register the DoWhy MCP v2 0 MCP server in PolicyLayer and add a rule for fcm_discovery: 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 DoWhy MCP v2 0. Nothing to install.

What risk level is fcm_discovery? +

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

Can I rate-limit fcm_discovery? +

Yes. Add a rate_limit block to the fcm_discovery 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 fcm_discovery completely? +

Set action: deny in the PolicyLayer policy for fcm_discovery. 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 fcm_discovery? +

fcm_discovery is provided by the DoWhy MCP v2 0 MCP server (lesong36/dowhy_mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.