build_c906 · XR875 Build MCP: Risk & Policy

WHAT IT DOES

What build_c906 does on XR875 Build MCP

AI agents invoke build_c906 to trigger actions in XR875 Build MCP. 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 IT NEEDS A POLICY

Why build_c906 needs a policy

This tool executes shell commands to compile firmware for an embedded system (C906 core). Execution of build commands can produce arbitrary binary artifacts whose behavior depends on the underlying source code, posing risk if an AI agent misconfigures build parameters or targets.

From the tool's definition Tool description explicitly states 'Build the C906 core (lunch_rtos 34 && m clean && m)' — the parenthetical reveals shell command execution with &&-chained operations (lunch_rtos, m clean, m), indicating execution of arbitrary build commands.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

build_c906 Rate-limited

build_c906 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.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "build_c906": {
      "limits": [
        {
          "counter": "build_c906_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches XR875 Build MCP, so you can run agents against it safely.

FAQ

Questions about build_c906

What does the build_c906 tool do? +

Build the C906 core (lunch_rtos 34 && m clean && m). It is categorised as a Execute tool in the XR875 Build MCP MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on build_c906? +

Register the XR875 Build MCP server in PolicyLayer and add a rule for build_c906: 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 XR875 Build MCP. Nothing to install.

What risk level is build_c906? +

build_c906 is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit build_c906? +

Yes. Add a rate_limit block to the build_c906 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.

How do I block build_c906 completely? +

Set action: deny in the PolicyLayer policy for build_c906. 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.

What MCP server provides build_c906? +

build_c906 is provided by the XR875 Build MCP server (unicorn2439614256/xr875-build-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.