build
Runs a build command and returns structured success/failure with errors and warnings.
This record as markdown: /tools/io-github-dave-london-build/build.md
What build does on Build
AI agents invoke build 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 build is rated High
Build commands can execute arbitrary code during compilation, invoke package managers, modify the filesystem, and trigger external tools. While the output is structured and read-only, the action itself (running a build) is an external operation with side effects that cannot be predicted from the tool name alone. This fits Execute rather than Read.
From the tool's definition Tool description states it 'Runs a build command' — this is code execution. The tool accepts command arguments (implied by 'tsc, generic commands' in server description) and triggers external build operations whose effects depend on those arguments.
Attacks that exploit this kind of access
The rule that runs build 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 build, this is the rule to start with:
build 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 build call is checked against it from then on.
Questions about build
Runs a build command and returns structured success/failure with errors and warnings. 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 build: 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.
build 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 build 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 build. 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.
build 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