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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful behavior beyond that: the ordering (newest first) and the meaning of each stage value (brief, review = waiting for approval, create = approved), which an agent needs to interpret results.

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?

A single front-loaded sentence with no waste; the ordering, contents, and stage glossary are packed efficiently without repetition.

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 no output schema, the description rightly carries the burden of explaining return contents, including decoding the stage field, which is the most valuable detail. It stops short of noting pagination or list-size limits, but for a user-scoped mascot list that is a minor 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?

There are zero parameters, so per the rubric the baseline is 4. The description spends its words on return semantics rather than params, which is appropriate here.

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 states the specific resource (the user's mascots) and describes the returned contents (stage, stills, animations), so the agent knows exactly what this call yields. It does not explicitly distinguish itself from siblings like create_mascot or approve_mascot, but the 'list' framing makes the distinction reasonably clear.

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 only implied: an agent infers from the name and zero-parameter schema that this enumerates mascots. The stage semantics ('review = waiting for approval') hint at a natural next step toward approve_mascot, but no when-to-use or alternative is named explicitly.

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