Fetch a URL from a remote host, optionally through a proxy, and report HTTP status, response time, and egress IP to verify connectivity and routing.
From a host, fetch a URL (optionally via a proxy) and report HTTP code, time and the egress IP.
| Name | Required | Description | Default |
|---|---|---|---|
| url | Yes | ||
| host | Yes | ||
| proxy | No | curl -x value, e.g. http://127.0.0.1:10809 or socks5h://127.0.0.1:1080 | |
| timeout | No | ||
| egress_ip | No | Also look up the egress IP via api.ipify.org |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the full burden. It does disclose the returned payload and that the probe performs an outbound call (egress IP lookup), which hints at an external dependency, but it says nothing about request method, redirect handling, failure/timeout behavior, or what privileges the 'host' requires.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
One sentence, zero filler, with the host scope and the proxy option front-loaded and the outputs listed last. Nothing repeats the title and nothing could be cut without losing information.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
With five parameters, no annotations, and no output schema, the description should be doing more work. It summarizes the return values, which is helpful, but omits error behavior, request method, and what the timeout actually bounds, so an agent cannot fully predict what a call will do or return in edge cases.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 40%: proxy and egress_ip are already documented in the schema, and the description only restates them ('optionally via a proxy', 'report ... the egress IP'). It does add one useful semantic — that 'host' is the machine the fetch originates from — but leaves url format and the timeout parameter (default 15, max 120) entirely to the schema.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description pairs a specific verb (fetch) with a specific resource (a URL) and a scoping qualifier ('from a host'), then names the outputs. That is far more precise than a generic 'run command', though it never explicitly contrasts itself with the sibling exec tool, which could also perform an HTTP fetch.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
Usage is only implied: 'from a host' and 'via a proxy' suggest remote connectivity testing, so an agent can infer this is the structured probe rather than a shell command. There is no explicit when-to-use, no when-not-to-use, and no named alternative among exec/docker_exec/xui_api.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.