lookup_by_portLook up the application and registration details for any specific port number from the centralized port allocation registry.
Look up information about a specific port.
| Name | Required | Description | Default |
|---|---|---|---|
| port | Yes | The port number to look up. |
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations exist, so the description carries the burden of behavioral disclosure. It implies a read operation via 'look up' but does not mention potential errors, whether the port must already be registered, or any guarantee about side effects.
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?
The description is a single efficient sentence with no filler or redundant phrasing. The core action and resource are front-loaded and immediately understandable.
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?
The tool is simple, has full schema coverage, and has an output schema, so the description covers the basic operation. However, it lacks usage guidance relative to sibling tools and behavioral caveats that would make it fully self-sufficient.
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 description coverage is 100% and the port parameter is clearly documented as 'The port number to look up.' The description adds no additional parameter meaning, but the schema already provides sufficient semantics.
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 uses a clear verb ('look up') and resource ('information about a specific port'), making the core purpose understandable. It distinguishes itself from the register/unregister siblings and from get_free_port, though it does not explicitly contrast with lookup_by_application.
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?
No guidance is provided about when to use this tool versus lookup_by_application or get_free_port. Given the sibling tools, the agent must infer the appropriate lookup scenario without explicit direction.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.