marketplace-probe
Send an HTTP request to an endpoint and inspect the response.
This record as markdown: /tools/dev-forgesworn-bray/marketplace-probe.md
What marketplace-probe does on Nostr Bray
AI agents invoke marketplace-probe to trigger actions in Nostr Bray. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call: builds kicked off, notifications sent, workflows started.
Why marketplace-probe is rated High
Making arbitrary HTTP requests to external endpoints is an Execute-category action: it triggers network operations with side effects that vary by argument (GET vs POST, target URL, payload). While described as 'probe/inspect', the tool sends real requests that could trigger state changes on remote systems. Severity is medium because the blast radius depends on what endpoints are targeted and with what methods.
From the tool's definition 'Send an HTTP request to an endpoint and inspect the response' — actively triggers external HTTP operations whose effects depend on the target endpoint and method
Attacks that exploit this kind of access
The rule that runs marketplace-probe 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 marketplace-probe, this is the rule to start with:
marketplace-probe stays usable, but rate-capped: a runaway agent can't fire it dozens of times 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 marketplace-probe call is checked against it from then on.
Questions about marketplace-probe
Send an HTTP request to an endpoint and inspect the response. It is categorised as a Execute tool in the Nostr Bray MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the Nostr Bray MCP server in PolicyLayer and add a rule for marketplace-probe: 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.
marketplace-probe is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.
Yes. Add a rate_limit block to the marketplace-probe 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 marketplace-probe. 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.
marketplace-probe 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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