blossom-servers
Read or update your preferred blossom server list (kind 10063). Without servers parameter, reads the current list. With servers parameter, publishes a new list.
This record as markdown: /tools/dev-forgesworn-bray/blossom-servers.md
What blossom-servers does on Nostr Bray
AI agents use blossom-servers to create or update resources in Nostr Bray, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Nostr Bray environment.
Why blossom-servers is rated Medium
The tool primarily serves as a configuration writer that publishes/updates user preference data (blossom server list) to a decentralized network. While it can read the current list, the ability to 'publish a new list' constitutes a reversible data modification. This is categorized as Write rather than Read because the update/publish functionality is its key feature.
From the tool's definition Tool description states it can 'Read or update your preferred blossom server list (kind 10063)'. The phrase 'publishes a new list' with the 'servers parameter' indicates the write capability.
Attacks that exploit this kind of access
The rule that runs blossom-servers 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-servers, this is the rule to start with:
blossom-servers stays usable, but capped: an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.
The button opens the PolicyLayer dashboard: create your workspace, connect Nostr Bray, apply this rule, and every blossom-servers call is checked against it from then on.
Questions about blossom-servers
Read or update your preferred blossom server list (kind 10063). Without servers parameter, reads the current list. With servers parameter, publishes a new list. It is categorised as a Write tool in the Nostr Bray MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Nostr Bray MCP server in PolicyLayer and add a rule for blossom-servers: 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.
blossom-servers is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the blossom-servers 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.
Set action: deny in the PolicyLayer policy for blossom-servers. 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.
blossom-servers 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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