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

Annotations already declare readOnlyHint=true, destructiveHint=false, and idempotentHint=true, covering the safety profile. The description adds the nature of the returned data (counts, percentages, per-aircraft-type breakdown), which is useful context beyond the annotations. No contradictions found.

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 two sentences with no filler. The usage trigger is front-loaded, followed by a compact summary of the output and a clear redirection to an alternative. Every sentence earns its place.

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 read-only stats tool with no parameters and no output schema, the description fully covers when to use it and what it returns. The annotations handle safety, and the description handles selection criteria. Nothing an agent needs to decide is missing.

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 tool has zero parameters, so the schema provides complete coverage. Per the rubric, a baseline of 4 is appropriate since there is no ambiguity to resolve and the description doesn't need to add parameter-level details.

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 uses the specific verb 'returns' and clearly identifies the resource as 'Starlink installation counts and percentages' across fleets. It distinguishes this tool from check_flight explicitly by stating 'Not for per-flight checks', making the purpose unambiguous.

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?

It gives an explicit trigger ('when the user asks...') and an explicit exclusion ('Not for per-flight checks — use check_flight for that'), naming the alternative. This provides clear guidance on when to select this tool over siblings.

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