fork_spec · Speclib MCP: Risk & Policy

WHAT IT DOES

What fork_spec does on Speclib

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

WHY IT NEEDS A POLICY

Why fork_spec needs a policy

fork_spec creates/modifies data (a new spec resource with changed visibility and authorship metadata) but does not permanently delete or destroy the original spec. It is reversible—the forked copy can be deleted. This is a Write operation rather than Destructive.

From the tool's definition Tool creates a new private copy of a spec ('Fork a spec into your own private copy') with modified metadata (visibility set to private, email as author). This is a reversible creation operation.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

fork_spec Rate-limited

fork_spec 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": {
    "fork_spec": {
      "limits": [
        {
          "counter": "fork_spec_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 Speclib, so you can run agents against it safely.

FAQ

Questions about fork_spec

What does the fork_spec tool do? +

Fork a spec into your own private copy. The forked spec gets visibility set to private and your email as author. Requires SPECLIB_API_TOKEN. It is categorised as a Write tool in the Speclib MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on fork_spec? +

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

What risk level is fork_spec? +

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

Can I rate-limit fork_spec? +

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

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

fork_spec is provided by the Speclib MCP server (rang501/speclib-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

// THE FULL RECORD

fork_spec is one line of Speclib's registry record.

The record carries the whole server: verified identity, auth posture, risk grade, every tool classified, recommended policy — re-checked continuously.

Teams ship this data inside their own products. See what a licence covers →