kb_tag

Add or remove tags on an existing entry.

SERVERPersistent Kb SOURCE0x67108864/persistent-kb-mcp

Medium RISK CLASS

Category Write

Parameters 00 required

Recommended Rate-limitedsee the rule below

Registry record Grade D, identity unverified Pull the record →

This record as markdown: /tools/0x67108864-persistent-kb-mcp/kb-tag.md

WHAT IT DOES

What kb_tag does on Persistent Kb

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

RISK

Why kb_tag is rated Medium

This tool modifies existing data (tags on entries) but does not delete entries or execute code. Tag changes are reversible (tags can be re-added or re-removed), placing this squarely in the Write category. Blast radius is low since it only affects metadata tagging within a local SQLite knowledge base.

From the tool's definition "Add or remove tags on an existing entry" — modifies tag metadata on an existing knowledge base entry reversibly

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs kb_tag safely

PolicyLayer is an MCP gateway: it sits between your AI agents and Persistent Kb, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For kb_tag, this is the rule to start with:

kb_tag Rate-limited

kb_tag 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": {
    "kb_tag": {
      "limits": [
        {
          "counter": "kb_tag_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect Persistent Kb, apply this rule, and every kb_tag call is checked against it from then on.

FAQ

Questions about kb_tag

What does the kb_tag tool do? +

Add or remove tags on an existing entry. It is categorised as a Write tool in the Persistent Kb MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on kb_tag? +

Register the Persistent Kb MCP server in PolicyLayer and add a rule for kb_tag: 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 Persistent Kb. Nothing to install.

What risk level is kb_tag? +

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

Can I rate-limit kb_tag? +

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

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

kb_tag is provided by the Persistent Kb MCP server (0x67108864/persistent-kb-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

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