port_scan

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

With no annotations, the description carries the full burden. It discloses the active nature, the TCP-connect method, and the default behavior of scanning common ports. It also flags authorization needs via 'needs scope', which is valuable behavioral context beyond the schema.

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, front-loaded sentence followed by a brief scope note. Every word earns its place, with no redundancy or filler.

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?

For a simple two-parameter tool, the description covers the essential behavior, default logic, and authorization requirement. An output schema exists, so the description need not enumerate return values. Minor gaps like listing the common ports are not critical.

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?

The schema provides no descriptions for 'host' or 'ports', and coverage is 0%. The description compensates by linking 'host' to 'a host' and explaining that 'ports' defaults to common ports when null. This adds meaningful semantics, though it does not detail array format or valid ranges.

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 clearly states the tool performs a TCP-connect scan on a host to identify open ports, which is a specific verb and resource. This distinguishes it from sibling tools like dns_lookup or http_probe, which have different purposes.

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?

The description provides clear context by noting the scan is 'active — needs scope', indicating it requires authorization and is not passive. However, it does not explicitly mention alternatives or when not to use it, though the context implies it is for port enumeration.

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