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

Annotations already establish read-only, idempotent, non-destructive, closed-world behavior, so the description earns credit for adding traits beyond them: newest-first ordering, the one-hour validity of preview links (an ephemeral-URL caveat), and the default kind being pictures. These are genuinely useful behavioral details for an agent.

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?

Two dense sentences that are front-loaded with the core purpose and then add sorting, search, filter, and ID details. Every clause carries information; minor density but no 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?

With six parameters, no output schema, and only 67% schema coverage, the description does well by describing what each returned item carries (media_asset_id, hour-limited preview link). It stops short of covering pagination/limit defaults, the one remaining 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?

Schema coverage is 67%, so the schema already documents kind, artist, and search. The description reinforces category and search intent but does not explain limit/offset pagination, which the schema leaves undocumented. Baseline 3 is appropriate given partial schema coverage with no compensating detail for the pagination parameters.

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 concrete verb+resource (lists the artist's pictures/videos in the Library) and adds scope qualifiers: newest-first ordering, searchability, and category filtering. It implicitly distinguishes itself from other list_* siblings by tying the output to update_post, though it does not name those siblings directly.

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?

Usage is implied through feature description (search by name, filter by category) and the note that media_asset_id is what update_post takes, which hints at the downstream workflow. However, there is no explicit when-to-use/when-not statement or named alternative (e.g., find_online) to route the agent.

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