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

Beyond the readOnlyHint annotation, the description discloses that the tool returns a reason rather than a simple boolean, and that the typical result is 'yes but with a payload penalty.' It also adds reliability caveats ('Indicative broker estimate', 'Not an offer of air transportation'), which an agent should know before relying on the result.

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 front-loaded with purpose and output behavior, followed by necessary caveats. The legal/broker disclaimers are somewhat verbose but are relevant to the tool's advisory nature; each sentence contributes meaningful context without obvious redundancy.

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 there is no output schema, the description adequately explains what the tool returns (a reason, not just a boolean) and the common shape of that reason. It also conveys the tool's advisory scope and limitations, which is important for a broker-related feasibility check. Minor gaps like error behavior or exact output structure are 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?

Schema coverage is 100%, with both parameters documented in the input schema. The description adds context about what the tool evaluates (elevation, wingspan, weight) but does not add new detail about the format or syntax of the icao or aircraft parameters beyond what the schema already provides.

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 predicate: determines whether one aircraft can use one airfield, with explicit evaluation criteria (elevation, published wingspan, weight limits). This clearly distinguishes it from siblings like estimate_flight_time, get_quote, list_aircraft, and search_airports.

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 implies use as a planning aid and explicitly excludes it as a final authority ('operating carrier and its pilot in command decide'). However, it does not mention when to choose this tool over sibling tools or name alternatives, so usage guidance remains somewhat implicit.

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