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

Annotations already declare readOnlyHint, idempotentHint, and openWorldHint=false, so the safety profile is covered. The description adds the 'currently published' scoping constraint, which is useful, but it does not disclose return shape, ordering, or failure behavior. This is acceptable given the strong annotations.

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?

A single sentence with every word contributing: verb, range, qualifier, resource, and key. It is front-loaded and free of filler.

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 simple one-parameter read-only tool with an idempotency guarantee, the description provides enough to invoke correctly: what to pass, how many, and in what scope. It could mention return format, but the absent output schema and simple complexity keep this from being a major gap.

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?

With 0% schema description coverage, the description carries the full semantic burden. It clarifies that the IDs are public IDs (not internal identifiers) and that two to five are expected, which is meaningful beyond the raw array schema. It doesn't specify ID format, but the semantic is sufficiently clear.

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 names a specific verb (Compare), a bounded resource (currently published Gkmex cranes), a count (two to five), and a key (public ID). This clearly distinguishes it from get_crane (single crane) and list_cranes (enumerate cranes).

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 usage context is clear: use when comparing multiple published cranes by their public IDs. It does not explicitly name sibling alternatives or exclusions, but the tool's stated scope and the two-to-five constraint make the appropriate scenario evident.

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