create_field · GitHub Projects MCP Server MCP: Risk & Policy

WHAT IT DOES

What create_field does on GitHub Projects MCP Server

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

WHY IT NEEDS A POLICY

Why create_field needs a policy

This tool performs a create operation that modifies project structure by adding a new field. It is reversible (can be deleted), so it qualifies as Write rather than Destructive. Severity is medium because unauthorized field creation could disrupt project organization and workflow, but the impact is limited to project metadata and is easily undone.

From the tool's definition Tool creates a new custom field in a GitHub Project V2, as stated in the description: 'Create a new custom field in a GitHub Project V2'. The action is reversible via delete_field (sibling tool), making it Write rather than Destructive.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create_field Rate-limited

create_field 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": {
    "create_field": {
      "limits": [
        {
          "counter": "create_field_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 GitHub Projects MCP Server, so you can run agents against it safely.

FAQ

Questions about create_field

What does the create_field tool do? +

Create a new custom field in a GitHub Project V2. It is categorised as a Write tool in the GitHub Projects MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on create_field? +

Register the GitHub Projects MCP Server MCP server in PolicyLayer and add a rule for create_field: 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 GitHub Projects MCP Server. Nothing to install.

What risk level is create_field? +

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

Can I rate-limit create_field? +

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

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

create_field is provided by the GitHub Projects MCP Server MCP server (lexmata/github-projects-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.