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

This description is excellent for behavioral transparency because it discloses crucial operational details not covered by the schema or annotations, specifically the cost (10 tokens per call) and the behavior for null/empty results (free).

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 highly concise. It uses two short, punchy sentences to communicate the primary functionality, the specific data points returned, and operational costs.

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?

Given the function (reliability metrics), the description is complete regarding the data provided. The agent knows exactly what information to expect and the financial implications (cost). The only minor gap is the lack of defined return structure, which is common.

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 100%, meaning the input fields are fully defined structurally. The description only serves to reiterate that the input is tied to a specific carrier/SCAC.

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 purpose is to provide 'on-time performance and delay distribution' and specifies the scope is for a 'specific carrier (by SCAC)', making it highly actionable and specific.

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?

While the tool's name implies its usage, it does not explicitly state when to use it versus alternatives like 'get_schedules' or 'carrier_league' in the sibling set.

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