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

The description says 'call this IMMEDIATELY' and instructs to estimate duration, but does not disclose any behavioral aspects like whether the tool performs network calls, requires authentication, or has side effects. Since no annotations are provided, the description carries the full burden, and it fails to disclose basic operational behavior beyond the trigger conditions.

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 verbose and front-loads imperative commands in all caps, which is redundant. It repeats the instruction to estimate durationHours and uses excessive emphasis. The key information about the two types of hours is buried near the end. It could be condensed into two clear sentences.

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 tool's simplicity (3 optional parameters, no output schema), the description covers the main use case and the distinction between the two duration parameters. However, it lacks any mention of what the response format is (e.g., estimated cost in what currency) and does not specify whether aircraftId is necessary for a cost estimate, leaving some gaps for an agent.

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%, so the schema already documents the parameters (aircraftId, durationHours, blockDurationHrs). The description adds guidance on how to estimate durationHours and explains the difference between durationHours and blockDurationHrs, which is useful. However, it does not clarify how aircraftId affects the cost or provide examples, so it adds some value but not extensive.

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 the tool's purpose: estimating flight cost when the user asks about cost. However, it does not explicitly mention the resource (flight cost) in a concise way and leans heavily on imperative instructions rather than a clear declarative statement. It is distinguishable from siblings by its focus on cost estimation, but the wording is muddled.

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 explicit usage triggers ('If the user asks

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