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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description does not add behavioral details beyond what annotations provide, which is acceptable but doesn't enhance transparency.

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 sentence, efficiently conveying the core purpose. While concise, it lacks additional context that could be added without becoming verbose, but it achieves front-loading.

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 existence of multiple sibling flight tools (cheap, search, popular) and a detailed input schema, the description is insufficient for an agent to understand what a 'calendar' entails (e.g., daily prices, format). The output schema exists but the description still underperforms in differentiation.

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%, with each parameter having a description. The tool description adds no additional semantic meaning for parameters, so it meets the baseline for well-documented schemas.

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 gets a flight price calendar for a route. It is specific and uses a verb+resource structure, but does not differentiate from sibling tools like 'aviasales.flights.cheap' or 'aviasales.flights.popular', which also return pricing information.

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 on when to use this tool versus alternatives. The description provides no criteria for selecting 'calendar' over other flight tools, leaving the agent without direction for comparison.

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