key-decrypt

Decrypt an ncryptsec (NIP-49) with a password. Returns the derived pubkey for verification — never the raw key.

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-decrypt.md

WHAT IT DOES

What key-decrypt does on Nostr Bray

AI agents call key-decrypt 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-decrypt is rated Low

This tool performs cryptographic decryption to retrieve a public key for verification. It is read-only in nature—it queries/derives data without side effects, does not modify state, does not execute external commands, and explicitly states it does not return the raw private key.

From the tool's definition Tool description states: 'Decrypt an ncryptsec (NIP-49) with a password. Returns the derived pubkey for verification — never the raw key.' The tool retrieves/derives a public key from encrypted data for verification purposes without modifying, deleting, or…

Attacks that exploit this kind of access

RECOMMENDED RULE

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

key-decrypt Allowed

key-decrypt 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-decrypt": {}
  }
}

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-decrypt call is checked against it from then on.

FAQ

Questions about key-decrypt

What does the key-decrypt tool do? +

Decrypt an ncryptsec (NIP-49) with a password. Returns the derived pubkey for verification — never the raw key. 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-decrypt? +

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

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

Can I rate-limit key-decrypt? +

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

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

key-decrypt 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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