handler-discover

SERVERNostr Bray SOURCEnostr-bray

Low RISK CLASS

Category Read

Parameters 00 required

Recommended Allowedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/dev-forgesworn-bray/handler-discover.md

WHAT IT DOES

What handler-discover does on Nostr Bray

AI agents call handler-discover to retrieve information from Nostr Bray without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

RISK

Why handler-discover is rated Low

This tool queries Nostr events (kind 31990) to discover available handlers and their metadata. It has no side effects, creates no data, executes no code, and does not irreversibly modify state. The action is passive discovery/enumeration of existing information, which is characteristic of a Read operation. Low severity because discovering handler metadata poses minimal risk even if misused by an AI agent.

From the tool's definition Tool description states it 'Discovers' and 'Searches for' and 'Returns handler names, descriptions, supported kinds, and transport endpoints' — purely informational retrieval with no modification, deletion, or execution.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs handler-discover 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 handler-discover, this is the rule to start with:

handler-discover Allowed

handler-discover is read-only, so it stays allowed. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "handler-discover": {}
  }
}

ALLOW ONLY THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect Nostr Bray, apply this rule, and every handler-discover call is checked against it from then on.

FAQ

Questions about handler-discover

What does the handler-discover tool do? +

Discover MCP-capable handlers on Nostr. Searches for kind 31990 events that include mcp transport tags. Optionally filter by supported event kind. Returns handler names, descriptions, supported kinds, and transport endpoints. It is categorised as a Read tool in the Nostr Bray MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on handler-discover? +

Register the Nostr Bray MCP server in PolicyLayer and add a rule for handler-discover: 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 handler-discover? +

handler-discover is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit handler-discover? +

Yes. Add a rate_limit block to the handler-discover 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 handler-discover completely? +

Set action: deny in the PolicyLayer policy for handler-discover. 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 handler-discover? +

handler-discover 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.

KEEP EXPLORING

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