Skip to main content
Glama
Sign In
localhost-mcp

localhost-mcp

by HasanJahidul
OverviewSchemaSourceRelated ServersDiscussionsAdmin
TypeScript
Local

port_info

Read-onlyIdempotent

Inspect a specific TCP port to identify the dev server using it, or confirm the port is free. Helps resolve port conflicts before starting or stopping a process.

Instructions

Read-only. Inspects a single TCP port and reports the dev server holding it (same fields as list_dev_servers). If nothing is listening, or the listener is not a recognised dev process, returns { port, status: "free" }. Useful for answering "what's on :3000?" before starting or killing something.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "port": "<port>"
    },
    "name": "port_info"
  }
}

Input Schema

NameRequiredDescriptionDefault
portYesTCP port number, 1–65535, e.g. 3000.

Output Schema

NameRequiredDescriptionDefault
portNo
statusNo

Schema Changelog

Changes observed during successful MCP inspections.

  1. Changed2 schema fields changedv0.1.1
    • changedInput schema / properties / port / description
      Previous value: -"TCP port number"New value: +"TCP port number, 1–65535, e.g. 3000."
    • changedOutput schema / (root)
      Previous value: -nullNew value: +{
+  "description": "Either a dev-server record (see list_dev_servers) or `{ port, status: \"free\" }`.",
+  "properties": {
+    "port": {
+      "type": "number"
+    },
+    "status": {
+      "type": "string"
+    }
+  },
+  "type": "object"
+}
  2. First observedv0.1.0

TDQS

A4.3/5.0
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true, destructiveHint=false, idempotentHint=true, and openWorldHint=true. The description adds value by explaining the return format (same fields as `list_dev_servers`) and handling edge cases (nothing listening or not a recognised dev process). No contradiction with annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is three sentences, with the key verb 'Read-only' front-loaded. Every sentence adds necessary information: purpose, return format details, and usage scenario. No wasted words.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the presence of annotations (read-only, idempotent, non-destructive) and an output schema (implied), the description is complete. It covers behavior for all inputs (port in range) and edge cases (free port, unrecognised process). The tool's scope is well-defined.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% with a well-described parameter (port). The description adds 'TCP port number, 1–65535, e.g. 3000,' which mirrors the schema. Since the schema already does the heavy lifting, the description does not add significant new semantics beyond clarifying the example.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool inspects a single TCP port and reports the dev server holding it. It distinguishes from sibling tools like `list_dev_servers` (which lists all servers) and implies a specific function ('what's on :3000?').

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explicitly says 'Useful for answering "what's on :3000?" before starting or killing something,' which provides clear context for when to use. However, it does not explicitly mention when not to use or list alternatives, though sibling tool names provide some guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Deploy Server

Other Tools