Runs cargo check (type check without full build) and returns structured diagnostics. Faster than build for error checking.
AI agents invoke check to trigger actions in Http. 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.
The tool executes a cargo check command, which runs the Rust compiler's type-checking phase. While it doesn't produce a full build artifact, it executes an external process (cargo/rustc) that reads source files and performs analysis. It has no direct write/destructive effects, but executing arbitrary build tooling on potentially untrusted code could have side effects via build scripts (build.rs).
From the tool's definition Runs cargo check (type check without full build) and returns structured diagnostics
Documented attack patterns abuse exactly the kind of access check gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Http, and nothing reaches the server without passing your rules. This is the rule we recommend for check:
{
"version": "1",
"default": "deny",
"tools": {
"check": {
"limits": [
{
"counter": "check_rate",
"window": "minute",
"max": 10,
"scope": "grant"
}
]
}
}
}check 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.
Free to start. No card required.
Runs cargo check (type check without full build) and returns structured diagnostics. Faster than build for error checking. It is categorised as a Execute tool in the Http MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the Http MCP server in PolicyLayer and add a rule for check: 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 Http. Nothing to install.
check 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 check 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 check. 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.
check is provided by the Http MCP server (@paretools/http). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Http, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
202 Http tools catalogued and risk-classified — across an index of 43,000+ MCP servers.