canary-group-join

Join an existing CANARY group using a shared seed (received via NIP-17 DM).

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/canary-group-join.md

WHAT IT DOES

What canary-group-join does on Nostr Bray

AI agents use canary-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 canary-group-join is rated Medium

Joining a group is a reversible write action — it creates membership state on the Nostr network. It does not delete data, execute arbitrary code, or move money. The shared seed received via DM introduces some risk (potential for misuse if the agent joins unintended groups), but the action itself is a standard write/subscribe operation.

From the tool's definition Join an existing CANARY group using a shared seed (received via NIP-17 DM)

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs canary-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 canary-group-join, this is the rule to start with:

canary-group-join Rate-limited

canary-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": {
    "canary-group-join": {
      "limits": [
        {
          "counter": "canary-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 canary-group-join call is checked against it from then on.

FAQ

Questions about canary-group-join

What does the canary-group-join tool do? +

Join an existing CANARY group using a shared seed (received via NIP-17 DM). 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 canary-group-join? +

Register the Nostr Bray MCP server in PolicyLayer and add a rule for canary-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 canary-group-join? +

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

Can I rate-limit canary-group-join? +

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

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

canary-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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