bbs_learn_prompt · Mcp Bbs MCP: Risk & Policy

WHAT IT DOES

What bbs_learn_prompt does on Mcp Bbs

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

WHY IT NEEDS A POLICY

Why bbs_learn_prompt needs a policy

The tool writes (appends) data to a shared markdown catalog file. This is a reversible write operation — adding a prompt entry to a file. It does not execute code, delete data, or involve financial transactions. Severity is low since it only appends to a documentation/catalog file, though 'shared' nature means it could affect other users or agents reading from that catalog.

From the tool's definition Append a prompt entry to shared prompt-catalog.md

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

bbs_learn_prompt Rate-limited

bbs_learn_prompt 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": {
    "bbs_learn_prompt": {
      "limits": [
        {
          "counter": "bbs_learn_prompt_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 Mcp Bbs, so you can run agents against it safely.

FAQ

Questions about bbs_learn_prompt

What does the bbs_learn_prompt tool do? +

Append a prompt entry to shared prompt-catalog.md. It is categorised as a Write tool in the Mcp Bbs MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on bbs_learn_prompt? +

Register the Mcp Bbs MCP server in PolicyLayer and add a rule for bbs_learn_prompt: 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 Mcp Bbs. Nothing to install.

What risk level is bbs_learn_prompt? +

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

Can I rate-limit bbs_learn_prompt? +

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

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

bbs_learn_prompt is provided by the Mcp Bbs MCP server (livingstaccato/mcp-bbs). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.