key-public

Derive a public key (hex + npub) from a secret key (nsec or hex). WARNING: the secret key is transmitted through the MCP transport — use only for local/trusted setups.

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/key-public.md

WHAT IT DOES

What key-public does on Nostr Bray

AI agents call key-public 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 key-public is rated Low

This tool performs deterministic key derivation (a one-way mathematical operation on input to produce output) with no side effects on data or external systems. It is categorized as Read because it retrieves computed cryptographic material.

From the tool's definition Tool 'derives' a public key from a secret key — it retrieves/computes and returns cryptographic data without modifying, deleting, or executing external operations.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs key-public 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 key-public, this is the rule to start with:

key-public Allowed

key-public 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": {
    "key-public": {}
  }
}

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 key-public call is checked against it from then on.

FAQ

Questions about key-public

What does the key-public tool do? +

Derive a public key (hex + npub) from a secret key (nsec or hex). WARNING: the secret key is transmitted through the MCP transport — use only for local/trusted setups. 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 key-public? +

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

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

Can I rate-limit key-public? +

Yes. Add a rate_limit block to the key-public 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 key-public completely? +

Set action: deny in the PolicyLayer policy for key-public. 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 key-public? +

key-public 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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