nx
Runs Nx workspace commands and returns structured per-project task results with cache status.
This record as markdown: /tools/io-github-dave-london-build/nx.md
What nx does on Build
AI agents invoke nx to trigger actions in Build. 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 nx is rated High
The tool executes Nx workspace commands, which can trigger builds, tests, deployments, code generation, and other task runner operations. This constitutes executing external operations whose effects depend on the arguments passed. The blast radius is high because Nx commands can affect the entire monorepo workspace, run arbitrary scripts, deploy artifacts, or modify project files.
From the tool's definition 'Runs Nx workspace commands' — actively executes build/task runner commands in a workspace
Attacks that exploit this kind of access
The rule that runs nx safely
PolicyLayer is an MCP gateway: it sits between your AI agents and Build, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For nx, this is the rule to start with:
nx 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 Build, apply this rule, and every nx call is checked against it from then on.
Questions about nx
Runs Nx workspace commands and returns structured per-project task results with cache status. It is categorised as a Execute tool in the Build MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the Build MCP server in PolicyLayer and add a rule for nx: 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 Build. Nothing to install.
nx 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 nx 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 nx. 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.
nx is provided by the Build MCP server (Dave-London/Pare). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
More on Build, and thousands of servers like it.
Across the catalogue