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

No annotations are provided, so the description carries the full burden. It implies a read-only query by saying 'Return', but it does not disclose behavior for invalid or unsupported ports, error handling, or data freshness. For a simple lookup the basic transaction is adequately transparent.

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 compact and front-loaded, with two short sentences plus an args list containing only the necessary parameter explanation. No filler or redundant content.

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 one-parameter lookup with an output schema, the description adequately covers the input format and the purpose of the result. The only missing context is explicit routing to siblings or a note about supported-port preconditions, which is useful but not critical for invocation.

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 only describes port_id as a string, while the description adds essential semantic detail: it is a UN/LOCODE and provides concrete examples like 'BRSSZ' and 'CNSHA'. This fully compensates for the 0% schema description coverage.

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 states a specific verb ('Return') and resource ('predictive congestion signal for a single port'), which distinguishes it from the plural sibling get_ports_risk. Concrete UN/LOCODE examples further clarify what the tool operates on.

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?

'For a single port' provides clear context that this tool is for one port, implying the plural sibling would be used for multiple ports. However, it does not explicitly name alternatives or state exclusions such as checking list_supported_ports beforehand.

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