This record as markdown: /tools/io-github-portel-dev-ncp/publish.md
What publish does on Ncp
AI agents invoke publish to trigger actions in Ncp. 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 publish is rated High
Publishing a message to a RabbitMQ exchange triggers external operations — it sends data to a message broker that can fan out to multiple consumers, trigger downstream workflows, or cause side effects in other systems. This is not a simple data write within a contained system; it executes an external communication action whose effects depend on the message content and routing configuration.
From the tool's definition Publish message to RabbitMQ exchange
Attacks that exploit this kind of access
The rule that runs publish safely
PolicyLayer is an MCP gateway: it sits between your AI agents and Ncp, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For publish, this is the rule to start with:
publish 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 Ncp, apply this rule, and every publish call is checked against it from then on.
Questions about publish
Publish message to RabbitMQ exchange. It is categorised as a Execute tool in the Ncp MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the Ncp MCP server in PolicyLayer and add a rule for publish: 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 Ncp. Nothing to install.
publish 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 publish 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 publish. 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.
publish is provided by the Ncp MCP server (@portel/ncp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
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