write_data · ContextForge MCP Gateway MCP: Risk & Policy

WHAT IT DOES

What write_data does on ContextForge MCP Gateway

AI agents use write_data to create or update resources in ContextForge MCP Gateway — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your ContextForge MCP Gateway environment.

WHY IT NEEDS A POLICY

Why write_data needs a policy

The tool performs a write operation that creates or modifies data reversibly. It does not delete data (which would be Destructive), execute arbitrary code (Execute), involve financial transactions (Financial), or merely read data (Read).

From the tool's definition Tool name is 'write_data' and description states 'Write data to a worksheet', indicating the tool creates or modifies data in a worksheet without irreversible deletion.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

write_data Rate-limited

write_data stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "write_data": {
      "limits": [
        {
          "counter": "write_data_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

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

FAQ

Questions about write_data

What does the write_data tool do? +

Write data to a worksheet. It is categorised as a Write tool in the ContextForge MCP Gateway MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on write_data? +

Register the ContextForge MCP Gateway MCP server in PolicyLayer and add a rule for write_data: 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 ContextForge MCP Gateway. Nothing to install.

What risk level is write_data? +

write_data is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit write_data? +

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

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

write_data is provided by the ContextForge MCP Gateway MCP server (jrmatherly/mcp-context-forge). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.