group-join

Send a kind 9021 join request, optionally using a kind 9009 invite code.

SERVERNostr Bray SOURCEnostr-bray

Medium RISK CLASS

Category Write

Parameters 00 required

Recommended Rate-limitedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/dev-forgesworn-bray/group-join.md

WHAT IT DOES

What group-join does on Nostr Bray

AI agents use group-join to create or update resources in Nostr Bray, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Nostr Bray environment.

RISK

Why group-join is rated Medium

This tool creates or modifies data reversibly—it establishes a group membership relationship. It does not execute arbitrary commands, delete data, or move money. The use of Nostr protocol kinds (9021 for join, 9009 for invites) indicates it writes state to a decentralized social protocol.

From the tool's definition Tool sends a 'kind 9021 join request' which initiates group membership; described as an action that modifies the user's group membership state in a Nostr protocol context.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs group-join safely

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

group-join Rate-limited

group-join 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": {
    "group-join": {
      "limits": [
        {
          "counter": "group-join_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 Nostr Bray, apply this rule, and every group-join call is checked against it from then on.

FAQ

Questions about group-join

What does the group-join tool do? +

Send a kind 9021 join request, optionally using a kind 9009 invite code. It is categorised as a Write tool in the Nostr Bray MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on group-join? +

Register the Nostr Bray MCP server in PolicyLayer and add a rule for group-join: 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 Nostr Bray. Nothing to install.

What risk level is group-join? +

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

Can I rate-limit group-join? +

Yes. Add a rate_limit block to the group-join 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 group-join completely? +

Set action: deny in the PolicyLayer policy for group-join. 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 group-join? +

group-join is provided by the Nostr Bray MCP server (nostr-bray). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

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