zap-balance

Request wallet balance via NWC. Sends a get_balance request to the wallet service.

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/zap-balance.md

WHAT IT DOES

What zap-balance does on Nostr Bray

AI agents call zap-balance 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 zap-balance is rated Low

This tool reads wallet balance state via the NWC (Nostr Wallet Connect) protocol. It has no side effects, does not move funds, and does not modify any data. The blast radius of misuse is minimal: an attacker could learn a user's balance but cannot steal funds or trigger transactions. Classified as Read with low severity.

From the tool's definition Tool performs 'get_balance request to the wallet service' — a query operation that retrieves account balance information without modifying data or executing code on behalf of the user.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs zap-balance 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 zap-balance, this is the rule to start with:

zap-balance Allowed

zap-balance 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": {
    "zap-balance": {}
  }
}

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 zap-balance call is checked against it from then on.

FAQ

Questions about zap-balance

What does the zap-balance tool do? +

Request wallet balance via NWC. Sends a get_balance request to the wallet service. 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 zap-balance? +

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

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

Can I rate-limit zap-balance? +

Yes. Add a rate_limit block to the zap-balance 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 zap-balance completely? +

Set action: deny in the PolicyLayer policy for zap-balance. 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 zap-balance? +

zap-balance 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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