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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is settled. The description adds only that results come back 'with pagination support' and are 'detailed', which the schema's page/size fields already convey; it says nothing about result caps, match ranking, or auth scope.

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?

It is short and front-loaded, but the second sentence is punctuation-broken ('across ALL content types. images, videos, GIFs and documents.') and the content-type enumeration merely repeats the title and the contentTypes enum.

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 read-only, no-output-schema search tool, the description plus a very detailed schema covers what an agent needs to invoke it: what it searches, all content types by default, and that results are paginated. The missing pieces (what 'detailed information' means, match ordering) are minor given the schema richness.

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 description coverage is 100% and the parameter docs are unusually rich (sort warning about labelName vs the UUID 'name', token-budget advice on size, enum values for contentTypes). The description contributes no parameter meaning beyond 'by name', so the baseline 3 applies.

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 and resource ('Search or list creative assets in the library') plus the scope qualifier 'across ALL content types', which is more than a restated name. It does not, however, distinguish itself from nearby siblings such as fetch_creative_details or search_ads_by_names, so an agent cannot tell from the description alone which one to pick.

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 by 'Search or list ... by name' and the schema note that omitting creativeName lists all, but the description itself gives no explicit when-to-use, when-not-to-use, or alternative tool (e.g. fetch_creative_details for full asset detail). The agent must infer the routing from the schema fields.

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