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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds ordering semantics (newest first), returned fields, and an authorization/workflow prerequisite via the skill doc, which is genuine context beyond 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 purpose and filters are front-loaded in the first sentence, with usage and the prerequisite following. It is fairly dense with parenthetical enumerations, but every clause carries information.

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?

With an output schema present, listing return fields is mildly redundant, but the prerequisite skill-doc rule and the usage routing make the definition complete enough for an agent to call it correctly.

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 per-parameter descriptions and an enum, so the schema already documents kind, page, and search. The description restates the kind values and default but adds no syntax or edge-case detail beyond the schema.

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?

It names a specific verb (Search) and resource (the media library) and enumerates the searchable fields and returned fields, so an agent can distinguish it from siblings like upload-media or delete-media without opening the schema.

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 explicitly states when to use it (before upload-media, when the user refers to an existing image) and names the related sibling, plus gives a mandatory prerequisite (read the site-assets-contract skill doc first).

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