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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so safety is covered. The description adds genuinely new context: assets originate from a workflow's asset block, and the tool cannot upload binaries the user has not provided, which prevents a plausible agent misuse.

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?

Four sentences, each doing work, with the core purpose and URL payload front-loaded. The closing upload caveat is slightly tangential to 'list' but is high-value guidance, so it earns its place; structure is otherwise tight.

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, the description need not explain return values, and it still covers origin of assets, the URL of each item, filtering/pagination capability, and the upload limitation. Nothing an agent needs to call this correctly or interpret its role 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?

Schema description coverage is 100%, so page_size, page_token, slug_prefix, exact_slug_prefix and include_level_prefixes are all documented in the schema itself. The description only echoes the high-level capabilities ('slug-prefix browse and pagination') without explaining interactions such as how exact_slug_prefix modifies slug_prefix. Baseline 3 applies when the schema carries the weight.

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 (list binary assets on the media CDN) and adds the distinguishing payload detail that each asset comes with its absolute URL. It is clearly separable from sibling reads like get_asset and from non-binary list tools like list_datafiles.

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?

Gives concrete usage contexts: see what a workflow's asset block has already published, and fetch a URL to embed in a page. It also states an exclusion path — if the asset isn't listed, send the user to the dashboard to upload — but never names get_asset as the single-asset alternative, so the routing is not fully explicit.

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