blossom-usage

Check storage usage across blossom servers for a pubkey. Returns per-server blob count and total size, plus aggregate totals.

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/blossom-usage.md

WHAT IT DOES

What blossom-usage does on Nostr Bray

AI agents call blossom-usage 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 blossom-usage is rated Low

This tool retrieves and reports storage metadata for a given pubkey across blossom servers. It performs a read-only query operation with no side effects, no data modification, and no irreversible actions. The blast radius of misuse is minimal — an agent could only enumerate storage information already accessible to the queried pubkey.

From the tool's definition Tool description states 'Check storage usage' and 'Returns per-server blob count and total size' — purely informational queries with no modification, deletion, or execution.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs blossom-usage 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 blossom-usage, this is the rule to start with:

blossom-usage Allowed

blossom-usage 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": {
    "blossom-usage": {}
  }
}

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 blossom-usage call is checked against it from then on.

FAQ

Questions about blossom-usage

What does the blossom-usage tool do? +

Check storage usage across blossom servers for a pubkey. Returns per-server blob count and total size, plus aggregate totals. 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 blossom-usage? +

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

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

Can I rate-limit blossom-usage? +

Yes. Add a rate_limit block to the blossom-usage 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 blossom-usage completely? +

Set action: deny in the PolicyLayer policy for blossom-usage. 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 blossom-usage? +

blossom-usage 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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