check_package_version

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

Annotations already declare readOnly/openWorld/non-destructive, but the description adds real value: it discloses that the comparison is against live CRAN and explicitly disclaims local verification, preventing the agent from assuming it inspects the local library. It does not mention network-failure behavior or latency.

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 tight sentence with the core action front-loaded and the scope caveat immediately after; no filler and every clause contributes.

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?

An output schema exists so return values needn't be explained, and annotations cover the safety profile. For a two-parameter lookup the description is nearly sufficient, with only edge-case behavior (network failure, unparseable versions) left unaddressed.

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 0% and neither parameter is documented, so the description must compensate. It partially does by clarifying that installed_version is supplied by the caller and compared to CRAN rather than read from disk, but it gives no format or version-string syntax guidance for either parameter.

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?

States a specific verb (Compare) and resource (an R package version) and names the comparison baseline (CRAN), which separates it from siblings like get_package_info or search_packages. It stops short of explicitly differentiating itself from the closely related check_package_compatibility.

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?

"Client-supplied" implies this is for versions the caller already knows, not for probing a local install, which is useful implied context. However, no sibling is named as an alternative and there is no explicit when-not guidance (e.g. versus check_package_compatibility).

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