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

Annotations already establish read-only, non-destructive, closed-world behavior. The description adds value by clarifying that only registered public pages are accessible and that drafts/guides/submissions/unknown paths will not be found. This helps set agent expectations about what kinds of paths will fail without contradicting the 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?

The description is a single, well-structured sentence pair with no redundant wording. The primary action and scope are front-loaded, and the exclusion list follows naturally. Every clause 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 simple one-parameter read tool with an output schema and clear annotations, the description is complete. It covers the target resource, the lookup input, and the main failure categories. Return value details are already covered by the output schema, so nothing critical 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 schema provides zero description coverage for the path parameter, so the description must compensate. It adds meaning by specifying 'canonical path' and 'registered public page,' which is useful but still somewhat ambiguous—it does not give an example or format for a canonical path. The description partially compensates but leaves room for interpretation.

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 (retrieve), a resource (registered public page), and a key selection criterion (canonical path). It also lists what is excluded (drafts, guides, submissions, unknown paths), making the tool's scope unmistakable. This clearly differentiates it from the sibling tools, which involve asking, comparing, and searching.

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 clear context for when the tool applies: only published public pages with canonical paths. It explicitly states that drafts, guides, submissions, and unknown paths are unavailable, guiding an agent away from invalid calls. It does not name sibling alternatives, but the sibling tools are functionally distinct enough that no exclusion is necessary.

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